III}, IFIIMI PI”

1 1 II'II II WIII‘: I
”l; 11M1PWIM
“a II IIIIIIIII11

  

.WIIIIIII I-‘I'I IIIII I'III
1"11I11III1I 1 11111 1iI1IIEIII I III III;
111 11I1I1111II IIIIII I

     
   

 

 

I'IMI II

1 III In ”If: IIIIIIII III I
“I1 W ”I II11111II’1I. I1 :III

II.)

N
—-

     
  
    
    
    
   

_J

       

 

—.
a
. -
. - _
r- j _ I - __ .
fly ‘( fi— _
w“;— ' ' _ '
o
- _ -
.
t ‘ - .—
..

w a.
..."?1—*_ '
5 - -

‘1 D-
-V -
—1- .

 

flIIIWWWIfiW
I} II III . III 1I IIIIIIII I
III" III!” II IIIIIIIIIIIII III

:—

w

  
  
  

'__———. .1,
mg
m

5—5....

 

   
     
 

' '
-——-- _.__

v_h

 

*—

"4

w
;.;‘i

III

II IIIIIIIII II

I I1111‘III11I'IIII1J III”
II III I
II IIII’IIIIIIIIIIII

 
 

.'
—....
-

m... :1‘:_, A
w—
M.

4 -»-._._,.__-
- f 4.A _F .-
l ' u
w...—

 
  

I
I

“

.._,
3:2...—
- 331.; w

 
 

~_‘_\—
g.

- «m
1 ' V,‘ i
. -..
v ‘ C, -
.

-.-
-m
s

 
       
  
  

—. - ’

 
 

-
u _
...
a
w.o . ’
....

 
 
 

~24; "3 . :
l ‘ -

v..-
..I
d

- 4
. . .
..
~u.“
v...

    
 

III:
I!"

a-v

   
   

   

     

  
 

 

 
     
    

 

£13.“: :17“: III

III I' I. -
11“ III I II III I (I II1II-II’3IEI’III
IIflIII1I1IIIIII I 'I I II W’I ‘III III III :‘IIIIIII21g12
III I III I III IIIIII I IIIIIIIII III II I III I III‘IIIIIIIII I
II. I II "IIIIH 1I 1'11" fl IIIIIII‘ 1‘ F1741}. Il‘ulni‘I WI 1-1111tfi11kq
"‘JIIINIIIIH NIH IIIIIII M‘ H1 ’I‘IIII 1‘ I! I; 111‘11IIII1I1I11I'1IIII I?“ ‘1I11i'II1411fI1 ”1111”,};,II'IIIHSIJ‘iflIIfiIIEIEIgIgzaITI‘fiIi?thgqug
I 11I1 I II" II MINI {3351‘ '11,;IJI 3‘ [JU'IIIH
'IIIIIIIIIIIIIII I. III II III III II I "I II 'I'III'IIIIIIIII III III-II IIII‘IIIII I IN: I ‘
I. III‘IIIIIIJIIPIIH‘IUMIIII’III1 I I‘ “III“! IIIIII IIIIII‘II III1L1I1III II {L111 1 “IL 114'“ “III; I15 'I'MI: 11 '7' :51“ I
I MILIMI' ‘I' IiI'1‘I I‘I I‘III' ' II
III II I III I II 'I III IIIIIIIII’III II
.11 1“”‘II”' IIIIIIII 11' 111IIIII'I1‘I IIIIIIIIJIIIIIIII‘" III In II I‘ W“
' I“ III III III“ I IIIIII III III II I ”I III {‘faégIgIII‘II

1 III III I311 III III

I III.
.1111 II:."'.I'; I“! £,-I. W “III III11IL111t111I‘I II: I: ,-I1:~'IIiIg--;'IE $1.11 1. 11:1
1' I‘ 11111111“ III-I III III IIIII‘I‘I III II”: III III IIIII‘I‘II‘I’III‘: I‘

I’m II I‘ I11 :I 1”";
’I IIIIHIIIIII 1&1wa “III III'I IIIIII-I; “iii WI Si“ IIi-III MIT "I1 ‘35:: 4:“: ‘

    

 
     

 

III
I? H

  
 

mm m I

   

 

I L “a. 0 ca «0'ny

 

This is to certify that the

thesis entitled

COLOR AS A CUE TO ORIENTATION
IN THE GERIATRIC INSTITUTION

presented by

MARI LYN MOWAFY

has been accepted towards fulfillment }
of the requirements for l

M.S. HUMAN ENVIRONMENT a DESIG:

degree in

 

 

(MW

Major professor

Date II-I3-80

 

0-7639

OVERDUE FINES:
25¢ per dry per item

RETURNING LIBRARY MATERIAL§:
Place in book return tom
charge from circulation records

 

( I 3's“ q 3K1IOEQ6

 

 

 

I

3 mama
uJi‘G-r'w: £37? his A i .20
VII—‘3’, ". / ,n

1., LI, I_ oi<

I ,<_ 1‘ “ ‘

‘ " L 22':

[‘11/

[HT-CS «

Pr:\ ' ’
H e

© 1980

MARI LYN FRANKEN MONAFY

All Rights Reserved

COLOR AS A CUE TO ORIENTATION
IN THE GERIATRIC INSTITUTION

BY

Marilyn Mowafy

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF SCIENCE

Department of Human Environment and Design

1980

 

ABSTRACT

COLOR AS A CUE TO ORIENTATION
IN THE GERIATRIC INSTITUTION

.‘I

)
../ .3 «fg‘ 5‘

BY

Marilyn Mowafy

The institutionalized elderly may be characterized
as experiencing a loss of control in man/environment inter-
action and information exchange. One aspect of that
information is orientation to the physical milieu. This
thesis is organized to study the design element of color
as an orientational cue relative to the elderly individual's

ability to receive, detect, and perceive it. It is estab-

 

Lg lished that while color may possess orientational potential

its relevance to the elderly user is still unknown. The
ability of the individual to receive and detect colored

stimuli is studied, with available research indicating that

.n-f/

_ q “h “m
degeneration ofcpEe-receptor elements hould effect color
v. k ’_ -1 _ _ I_u - __M_Ff*_____\

vision. Nevertheless, the precise character of that degen-
*”""\
eration and its prevelance among the elderly has yet to be

 

 

 

established. Research on elderly perception is shown to be
\Virrelevant to the environmental designer's informational
needs. Throughout the thesis areas for future research are

suggested and potential research questions generated.

Rarely in one's lifetime does a person find
dedicated friends who care regardless of the
circumstances. To Dr. Robert Summitt and
Dr. Robert Moore I dedicate this thesis with
love.

ii

ACKNOWLEDGMENTS

The author wishes to express sincere appreciation
to her graduate committee members Dr. Barbara Stowe,
Dr. Gertrude Nygren, Dr. Duncan Case, and Mr. Richard
Graham for their kind assistance in her graduate studies
and thesis preparation. A special word of thanks goes to
Dr. Robert Summitt, thesis advisor, who balanced con-
structive criticism, with wit, support, and encouragement.
His dedicated guidance throughout the project aiding in
the blossoming of a simple idea. To her husband, Mohey,
there is a simple, but heartful, "thank you." And final—

ly, and to Dr. Robert Moore, "Bob, I did it."

iii

TABLE OF CONTENTS

Chapter

I. Introduction . .
Problem Area Definition .
Approach to Problem .
Organization of Thesis

II. Man-Environment Communication
Communication: Content and Code
Conclusion

III. Color as an Orientational Cue
Introduction .
Color and Communication . .
Color as a Cue to Orientation . .
1_ Color as a Cue to Spatial Form .
Color as a Cue to Meaningful
Information . . .
Color as a Cue to Congruency .
Color in the Geriatric Institution
§7Conclusion

IV. Human Color Vision .
Introduction . .
The Human Visual System .
The Pre- -Receptor Level
The Receptor/Transducer Level
The Neural- Network/Transmission
Level .
Human Color Vision
Color Vision Testing
Laboratory Assessment
> Clinical Assessment
‘> Conclusion

Color Vision Characteristics of a Geriatric

111V
Pomlletmnzn
The Aged Visual System .
.F The Pre- -Receptor Level

The Receptor/Transducer Level
The Neural Network/Transmission
Level

iv

76
78
78
87

88

1.

LIST OF TABLES

Clinical Tests Employed in Detection of Hue
Discrimination . . . . . . . . . .

75

DOOM?“

U1

LIST OF FIGURES

Generic Definition of Institution
Man/Environment Communication Exchange
The Coding Process

Absorption Spectra of Three Photopigments of the
Human Eye. After Kauffman (1977) .

Horizontal Section of a Developing Lens

The Design Process

vi

19
21
27

63
82

VI.

Results of Color Vision Testing
Clinical Assessment
Conclusion .

Conclusion

vii

88
95
98

CHAPTER 1: INTRODUCTION
QB

. ~ I e.”

I w.
The environment is organized as ingrigately and system-
atically as any spoken language. It has a system of
cues that tells us how to respond to particular situa-
tions. However, the environment communicates meaning-
fully only to the degree that the cues which are sent

out can be received and perceived by the individual.
(Pastalan, 1971, p. 4)

43

w

Wherever the social group is concerned for the welfare
of its members, it has been faced with the problem of caring
for its elderly. In the past this has not been a signifi-
cant problem because the older and weaker members of the
group usually died before their needs could become a burden
on the society. In this century, however, medical, tech-
nical, and social changes have led to an ever increasing
population of 325E32229§9219 (popularly defined as those age
65 and older), based on retirement statistics. The 1930

'\;;;s;;~pIa52d/the elderly population of the United States
at 6.6 million. By 1970, that number had increased to 19.8
million, with projections indicating that our total elderly
population will be 27.5 million by 1990. Furthermore, the
number of persons of old, old age (Neugarten, 1968) is also
increasing steadily. The 1930 data show that 29% of the
elderly were age 75+ and a negligible number at age 85. By
1970, these figures had grown to 38% and 6.7% respectively.
Although 95% of the present geriatric population maintains
adequate health and financial viability, which can be trans-

lated into independent or semi-dependent living arrangements,

the remaining 5%, totaling 1.5 million people, must reside

in an institutional setting. Moreover, it has been estimated
WW
that 40% of the elderly population at one time or another

will require institutionalization for some period of time

(Koff, 1977) Wtion occurs when the indi-

vidual experiences physical or mental deterioration, when
M M

 

 

 

he/she is isolated from the supportive services of family
and friends, or when there is insufficient political, econ-
omic, or social support in the community. These develop-
ments, characteristic of the aging process, have been sume
marized in the geriatric literature as a 'loss\pf~gontrgli_
or effectance in one's man/environment interactions (Schwartz
and Proppe, 1970).

There are many types of institutions currently avail-
able to the elderly which vary widely in the amount of sup-
portive services available to the resident. The essential
characteristics of the institution are: l) the dwelling
is designed for communal living, with varying amounts of
private space available to each resident and shared public
spaces; 2) the facility is designed to provide a support-
ive environment for the particular needs of its population;
and 3) it is designed for individuals who will reside there
for an extended period of time. The elderly individual

entering an institutional environment faces a new and com-

plex physical, social, and cultural milieu at a point in

 

time when his/her own energy resources are at a low ebb
because of the 'loss of control'. Therefore, it is the

responsibility of those involved in institutional design to

b
I ~19)":
“'. 1’ w ,
OI :‘ "‘ Via/II

W‘J‘iu“ N“ A. 3

105‘.

\

provide a physical milieu which will compensate for individ-
ual disabilities and lead to successful incorporation of the
individual into the institutional environment. The study of
institutional design only recently, however, has become a
topic of concern for the theorist, geriatric researcher,

and designer.

Problem Area Definition

 

Environmental theorists draw from a variety of disci—
plines to describe human adaptation to the environment as an
ongoing interaction and mutual modification process. These
theorists rely heavily on the basic tenet that the individ-
ual partakes in man/environment interaction by use of sen-
sory modalities in a stimulus/response mechanism. Extract-
ing evidence from physiology, psychology, and anthropology,
Amos Rapoport (1975), Alton J. DeLong (1974), and Edward T.
Hall (1969) have posited that one assimilates and shares
culturally the milieu of environmental stimulation in such
a way that thevbgiIfwenvironment is conceptualized as the
organization of time, space, communication, and meaning.
Furthermore, Roger Barker (1963) contends that human be-
havior patterns and milieu exist in aVsynomorphiclrelation-
ship. That is, human behaviors are inexorably linked to a
time-place-object framework called the behavior setting.
The built environment can then be conceived as a system of

potential physical resources capable of being endowed with

stimulus meaning by the user. Meaning is evaluated according

to effectance ability of the individual, termed 'sense of
competence' (Perin, 1970) in negotiating the physical and
social milieu in order to carry out everyday activities and
behaviors.

M. Powell Lawton (1977) has organized these theories
into an Ecological Model for the design of geriatric insti-
tutions. This model cguntgrbalances the individual's com-
petence (ability to perceive stimuli and respond to them)
with environmental press (impinging stimuli). Appropriate
competence/press interaction results in successfulcognition
of the behavior settingwandkadaptation. The elderly indi-

_ ~-'- HEM

vidual entering an institutional environment must partake of

 

an entirely new and different set of stimuli (press) and
his/her competence level is severely stressed. Inherent in
Lawton's model is the assumption that the designer, as or-
ganizer of environmental stimuli, manipulates the environ-

. . ' 3‘1 (We
ment 1n order to prov1de better congruence between competence

W _____

and press. This congruence, in principal, is the same pro-
cess underlying the concept of the 'progthe ic' environment

mi ’24 (4.29%)
(Lindsley, 1964). The intent of the prosthetic environment

 

 

 

is to 'fit' competence to press, either by effecting a

W m
change in the individual (e.g.,raising competence level) or
in the environment (e.g.,decreasing press). The goal of
the environmental designer, then, is to promote man/environ-
ment congruency by organizing a physical milieu that pro-
vides those resources necessary to enhance human competency.

One function of organized physical stimuli is to

provide the individual with orientatignalkgues_to thfehéh3:,.
viorflsettinng Webster's (1965) defines 'orient' as, "to
acquaint with the existing situation or environment". Orien-
tational cues in the environment serve as predictors of the
generic meaning of the behavior setting. They define the
space and its relevance to human needs and activities. To
facilitate effectance, such cues must allow rapid, unambig-
uous identification of their meaning. In the prosthetic
environment the designer employs redundant cueing systems to

a M—‘

enhance orientation. Because 'loss of control' involves
#,1—111_11,,rvefirr

‘mdiminished ability in detecting and perceiving stimuli,
E? redundantcueing systems use a variety of stimuli, acti-
vating diffefent sensory modalities, to communicate a single
meaning. It is a message amplification device. For the

elderly individual, amplification means decreased environ:
I.. ‘ I- '7 /

_\‘_~ u' 7 - -_.-~.._--____‘_/"_ -- -—-
mental press.aiii~»mwm-ahu
-1, -1. -- .1, -- ‘ M INK} \
ngé Redundant cueing syste s necessitate the simultaneous

_ __.—- and»

use of a variety of design elements such as size, shape,

light, color, and texture. It is, by definition, holistic. 9
W \

Nevertheless, appropriate use of redundant cues requires that
the designer be cognizant of the implications of tools em-

ployed. It requires a knowledge of sensation, perception,
W

and response processes. Design research, directed at spe-
\‘I'I’fi—M'
cific environmental stimuli can provide such knowledge.

 

This study is directed at the use of color as an orienta-
tional cue for use in the geriatric institution.

The designer employing color as a cueing mechanism

takes a serious approach to the design of colored environ-
‘ments in the realization of its potential as a tool enabling
effectance. Appropriate use of color for a geriatric popu-
lation requires an understanding of the informational char-
acter of color, the color detection abilities of the aged
visual system, and the perceptual experience of color in the

elderly. It draws on psychological, physiological, and

 

VC\ 1

—————__.

“WmOIEEiCiQ FEW A survey of psychological re-

 

search indicates that color not only communicates to the
individual on a variety of levels, but a1s0‘maywserygfiagw
an;orien£ational_sue_to the behavior setting by defining
space, enhancing focal points, and communicating affective
meanings about the environment. Geriatric researchers, how-
ever, have failed to investigate the informational character
of color for older people, preferring instead to generate
highly prescriptive uses of color based on color vision re-
search.

Human color vision always has held a fascination for
man, but only recent technological advances have permitted
serious investigation of the physiological elements of color
sensation. Those concerned with the physiological changes
which accompany aging have accumulated some data that char-
acterize the\degeneraEianmgfflthe;zi§ual‘system;r Those changes
affecting color vision specifically are: l) the pupil dia:

W
.vxnimeter diminishes with age, thus reducing total retinal illum-

V ‘I In!)
M
,flmk M”, -._. .

“‘1 1."

 
 

1/7

~—-

ination; and 2) lenticular light transmission is reduEe ,“M"
f W

with short wavelength light being_reduced to a greater

 

extent. Although current research on the visual system has

yet to achieve the sophistication necessary for conclusive
We

generalizations, most authors tend to agree with R. A.

Weale (1963) that degeneration of the ocular media, speci-
.1_\~,,___.___

». fically rigidity andCyellgwing)of the crystalline lens are

W M

the primary causes for the wavelength-specific decline in

color vision. Others, however, more recently are studying

the possibility that degeneration along the neural network ,4
Ww—w _. e - A ”1-1-11 1- -- .mp— _ _..__ ____ 2,“

also could be a contributing factor (Stordant, 1972). I

fir-“fl 1 M_-_‘,__ _____i ___, _.__‘_____‘_

There also have been several attempts in the last
fifty years to characterize geriatric color perception (2181
color detection). The study of color perception in general,
however, is still in its infancy and investigators not only
are wrestlingxwiEh—the multitude of variables inherent in
such a system, but also are attempting to correlate the find-
ings of various testing procedures in order to identify the
nature of perception that is being measured. fgeriatricv
studies have been plagued further by inadequate testing
procedures, small sample size, and a tendency to elaborate
on age differences between decades rather than concentrate
on the elderly. Nevertheless, their conclusions are in
general agreement with physiological studies in that they
indiE‘EE-W Partial"
larly at thexb1ne‘endggf_thgfi§pegtrum’(Lakowski, 1969).

Thus, the results of color vision research suggest

that elderly people may experience some difficulty in dis—

criminating hue, saturation, and value in the environment.
a n W-

W ‘
r—«v ‘-_ $.1- _.,_I . - -. . .. .—--.._, __ __ ___,_ I M I‘m—- ---- --.--—.-.— ..- .—...—._-

‘v \i-{A
/
.53( aesthetic liability but as a potential hazard hindering the

/7
’6

i

aha-kg,

It is the designer's responsibility in developing the pros-

[Z thetic environment to consider these difficulties not as an

 

elderly's effectance in behavior setting identification, and
thus, inhibiting appropriate man/environment interaction.

The design process initiates with problem definition
and proceeds to goal setting and information gathering.
Thus far, a situational context has been developed and a
problem area defined regarding the role of color in an insti-
tutional setting for geriatric users. Furthermore, an over-
riding goal, congruency development, has been established.
order to facilitate design implementation. Although speci-
fic goals would be set for a particular environment, five
general goals may be generated that would apply to all de-
sign problems regarding color in the geriatric institution.
They are:

1) Color should be used to facilitate_initial’adapta:’,
tion to the institutional environment. It has been noted in

fi___fi__1,##’”’
a wide variety 0 stu 1es that institutionalization is a

stressful event. Depression increases and mortality rates

W

may reach 50- 60% among relocated elderly during their first
”My”

year in the institution (Blenker, 1967). Initial adapta-

tion involves the user's ability to EriggE/Lgithexphygigalw

configuration of the space. One requires information from

Wmm~WH __ -J

the environment regarding the location and arrangement of

objects and spaces. This involves the use of color to

delineate areas such as unit wings or floors, room location,
level changes, exits, and so forth. Beyond location, how-
ever, it facilitates human movement through the spaces,

toward or around objects, by providing an orderly progression
MW

“M
\

Ofm5EEQEEEiEi§§1§E§MEEEEEEEEEL. Thus, color as a design tool
should be organized within and throughout the institution in
a_ratignal_grdggfito facilitate location recognition and di-
rectionality for movement.

2) Color should be used to fagilitatg_§ggial adapta-
tion within the institutional environment. Appropriate

F_fl,,.1

manipulation of the physical environment allows for a cer-
tain degree of satisfaction because physical needs are being
met. But man is a social being requiring ongoing interactions
‘with other people in order to enhance self-esteem and self—
actualization. Successful adaptation to an extended care
facility must involve\sggializa£ign;_ Therefore, a second
level of adaptation involves the user's ability to orient

to behavior settings in order to enhance person to person

communication. This involves the use of EEE9I~E9~39t only!

delineate location, but also activates the co itive and
W i
e onal reflexes of the individual to recognize the so:_

cially shared affective meaning of the spaces. Thus, color
_* __ -c..-.---——-“ W"M

 

 

 

—---.-—r..
Imam—v..- .,. _ .._—-——— __

r/d—m‘~ W

 

wshould be used to delineate a spatial framework, and also
provide a milieu of informational resources that facilitate
human interaction. This involves the use of color schemes
congruent to human behavior patterns such as stimulating

colors in a work environment and relaxing colors in rest

10

areas.

3) Color should be used to maintain a slightly higher
degree of press relative to user competence in order to maxi-
mize human potential for adaptation through growth. The
person entering an institution is stressed because the en-
vironment is totally‘ngw; Therefore, the initial phases of
adaptation to the environment require a degree of stability
in order to facilitate rapid assimilation of a wide variety
of information. In other words, environmental press should
be minimal to facilitate integration of a low competence
individual. But as adaptation proceeds, competence level
may also increase, so that the individual may desire greater
complexity and variety in the environment. A‘ESEEEE_E£_EEE}
lenge is required. This would allow for maximization of —
human potential and provide some stimulus for change and
growth. Thus, color should be organized in the environment
to communicate differences between behavior settings, but
also allow for some diversity and complexity within the
spaces. This necessitates the use of a broad range of
colors throughout the spectrum followed by variations in
value and saturation. Leon Pastalan (1979) has suggested
also that color schemes be devised that would change through
time (g;g; seasonal variations) in order to introduce com-
plexity as well as maintain reality orientation to events
occurring in the#gxtergal\gnyirggmgnt; In any case, the
use of color to provide complexity and variability in the

environment negates the possibility of simple color schemes

11

with merely focal point emphasis. It requires sensitivity
and a well developed plan for implementation.

4) Color should be used to provide an aesthetically
(~K_g III”-

 

pleasing environment that reflects user preferences and
TEIEEETT'XIEhohghIQ goal of any design is to provide an
aesthetically pleasing environment, the designer should be
cognizant that user preferences play an important role in
determining the final effect. Colors should be chosen to
provide not only for functional adaptation, but also for
perceived pleasantness to the geriatric users.

5) Color should beHWIWCWIfi-li;w

-Ei§§ifig£_§Eimulus detection. In order to facilitate adap-

 

tation to the physical arrangement of the space and its be-
havior settings, to provide for variety and complexity, and
to provide an aesthetically pleasing entity, the physical
stimulation must be detectable to the perceiver. This goal
may be conceived of as an enabler to achieving all other
goals. As noted, it may be deduced from the literature that
the elderly individual may perceive colors differently than
a younger person because of ontogenetic changes in the visual
system. If this is true, it is of utmost importance that
colors be selected relative to user capacity to receive and
detect them. Then, and only then, may the other goals be
achieved.

In order to achieve these goals, the designer requires
a considerable amount of information. But first a variety

of questions should be generated that would provide for

12

information gathering, analysis, and synthesis. The primary

questions to be answered are:

How does the individual interact with the environ—
ment in order to obtain needed information?

What is the form and content of information to be
transferred?

How may adaptation be evaluated?
DW

If so, what is the content of that information?

Is the content of that information the same for old
and young alike?

How may color as an informational cue be evaluated?
May color be employed to provide complexity and
variety?

What are geriatric user color preferences?

What are the parameters of elderly color vision capa-
bility?

What are the parameters of elderly color perception?

Given this information the designer could proceed to

generate alternative solutions to the design problem. This

requires

a broad review and summation of a wide variety of

research into perception, man/environment interaction, and

color as

an informational resource. To date, however, there

has been no serious effort to collect and review existing

theoretical and experimental data concerning the effect of

color and its usage for a geriatric population. The informa-

tion remains scattered and poorly related. Physiologists

13

have outlined the visual problems peculiar to a degenerating

visual system. Psychologists have documented the informa-
W W.

tional character of color as an orientational cue. And

4e—~———~11\h___,11_11,,11114—wr
environmental researchers have studied the impact of the

 

 

 

physical milieu on human behavior. But there has been no
attempt in the literature to correlate the geriatric per-
ception of color and the use of color as an environmental

cue affecting their behavior.

Approach to Problem

 

As stated, the designer should have accurate and
appropriate information concerning the visual characteris-
tics of the elderly in order to select color cues to code the
environment. He/she should also have reliable information
regarding the manipulation of color as an orientational cue
to the behavior setting. This information should include a
comprehensive review of the literature, the development of
statistically reliable research, and finally, a reliable
model to be used by the designer. Inasmuch as no such com-
pilation exists at this time, the objective of this study
is to assemble a complete and critical review of the state
of the art. This review studies available physiological,
psychological, and sociological data determining the role of
color in the built environment, the perception of color by
the elderly, and current views as to the use and applica-
bility of color cues in designing a prosthetic environment

that is sensitive to the needs and characteristics of the

14

elderly. The methodology employed in this study includes
extensive search of library resources as well as corres-
pondence and conversations with some of the major authors.
This study analyzes and discusses research techniques used
in the study of color and color vision and their reliability.
It is, therefore, an attempt to summarize the available
knowledge required to answer the above questions. Neverthe-
less, it will be shown in this paper that there are consid-
erable gaps in the information required. We need to know
much more before the design process may proceed. Therefore,
throughout the work further questions are generated that

suggest possible routes for future research.

Organization of Thesis

 

This thesis is divided into a series of chapters pro-
viding an ecological approach to the use of color in a ger-
iatric institution. Chapter 2 outlines a theoretical frame—
work of man/environment interactions and examines the
relevance of theory in geriatric research. Chapter 3 con-
centrates on the informational character of color through

W

a study of current psychological research. It then focusesfl

H—v—w

 

on the specific characteristics of color as an orienta—
-_1_1 -~11_1_1_._i~fl_—~—-~i_,ie-www

tional cue. The chapter ends with a discussion of current

 

 

 

 

 

 

views of color in the geriatric institution. Chapter 4
analyzes the human visual system, color perception mechan-
isms, and the methodology of color vision testing. Chapter
5 expands on this foundation to compile an objective review

of current research on geriatric vision and color perception.

15

It serves to identify methodological problems existing in
the literature that have led to an oversimplification of
the visual capabilities and needs of the elderly. The
final chapter of this thesis serves as a summation of the
state of the art, identifies unanswered questions, and sug-
gests future research avenues for the study of color as an

orientational cue in the geriatric institution.

CHAPTER 2: MAN/ENVIRONMENT COMMUNICATION

'Design' of the human environment implies a commitment
to maximizing human potentials and values. Achieving this
goal requires an understanding of the systemic relationship
of the individual and his/her environment. Humans are living
systems that experience their environment through metabolic
and sensory perceptual mechanisms. The environment can be
conceived as the organization of material and informational
resources in a spatial and temporal framework. At the inter-
face between the two systems, matter and information are
exchanged and transformed, resulting in a mutually modifying
relationship. The direction and flow of that exchange,
coupled with the systems' transformation capacity, will
determine ultimately the quantity and quality of human adap-
tation. The primary elements of concern that have been
identified in this study are the individual, the institu-
tional environment, and their communicational exchange at
interface. It is now necessary to define and characterize

these elements relative to an ecosystem approach.

1) The Environed System: The Individual

While the elderly population of this country clearly
is a heterogenous group, it is unified by its stage in the
human developmental process called aging. Aging is multi-
dimensional, affecting the physical, psychological, social,
and cultural processes of the human being. It is generally

characterized by the gradual or traumatic degradation of the

16

17

living system, described as a "loss of control or effective-
ness in the environment" (Schwartz gt 31, 1970, p. 230).
Loss of control is precipitated either by individual factors
(e;g;, loss of physical or mental acuity) or by environmental
factors (2181» loss of income, emotional ties, or role sta-
tus). Schwartz gt al have stated that the loss of control
contains at least three dimensions:
a) Barring catastrophy, loss of control usually
occurs in developmental increments so small as to
be imperceptible. Research_indigatesflth§t_§en;_g

sory sensitivity declines from age 30 until_death.

__ _. .—- :—

 

.-.....- .

rh-h_fi

fiSimiIarly, rolestatus and social integration are
usually highest in the productive middle years.
Thereafter, they also decline.

W"

b) Loss of control is multi-faceted including all

 

realms of the human system. Just asfidiminished

sensory acuity signifies loss of control, so too,
does the shrinking size of the individual's home
range.

c) Loss of control is_EEmul§£iyeia-Diminished sen-
sory sensitivity affects mobility in the home
range, territoriality, and social interaction.
The process can lead to alienation and 'disen-
gagement'.

Loss of control is, in and of itself, a highly nega-

 

tive concept. Nevertheless, purposeful man/environment

N.

“M.

intgfaEtions may inhibit or deter the cumulative effects of

18

this process, allowing for adequate matter and informational
exchange. The degree to which interaction controls this

process can be related to man/environment congruency.

2) The Environment: Institution

The American Heritage Dictionary defines institution

 

as "a place of confinement". Traditionally, the nursing
home or geriatric hospital has been viewed as a place of
confinement and 'where the old people go to die'. This
attitude was reinforced by institutions that served as
catch-alls for the old, mentally indigent, and orphaned, all
of whom were viewed by society as non-productive. In more
recent years, the elderly have been segregated and insti-
tutionalized in former low income housing projects, univers-
ity dormitories, and sanitaria when these buildings were
abandoned as inadequate for the original users. It appears
that, if confinement is the primary objective, any place
will do.

An ecological definition approaches this concept from
two levels. First of all, institution may be generically
defined as an organization established by humans to provide
access mechanisms for the fulfillment of human needs and
values. This implies a relationship of feedforward and
feedback in the interactiofi,Emiigu:E:E:EEmonstrates this
concept where E stands for the environment and O for the

M ~/\_/
human organism. Secondly, institution may be defined as a

bounded system serving as an environment for the individual

l9

r—RESPONSE——l
E O
L— MATTER J

INFORMATION

Figure 1: Generic Definition of Institution.

system or a collective group of individuals. In this sense,
it is an organized system with the goal of providing a sup-
portive milieu for the aged. The concept of the supportive
milieu (g;g;L prosthetic environment) assumes that environ-
‘mental input into the exchange process may be manipulated

relative to human capacity in order to enhance congruency.

3) Communication Exchange
All living 3 stems ar e dr' . From an eco-
logical standpoint, energy resources are of two types:

Jo “ o o o
matterJand 1nformat1on. Matter energy con51sts of f0331l
_. / “H - -

‘._,_

Md”

fuels, mechanically produced energy, goods, and services.

Information energy is composed of knowledge, ngrms, and

 

values. At interface, linkages are established that provide
for energy flow between the two systems. The primary concern
for the development of information exchange linkages is the
ability of both the individual and the environment to re-
ceive and code the communication of stimuli. Reception of
stimuli is based on the system's ability to detect its
existence in the milieu and to comprehend its relevance as

information. It relies on sensitivity of the receptor

I
;
/
\
\

\f‘\.

M /"'-‘
''''' fi’ Mb- mu“ 7 __, M

\.
E9/ it. In this instancégthe'envirOnment overwhelms the indi-
_.,,//”

20

system and is mediated by experience and established code.
Upon detection, the system develops codes whereby the stimuli
are organized, condensed, and given meaning. In the man/
environment interface, information transfer flows in both
directions. For example, the individual receiving stimuli
from the environment develops codes concerning locations and
relationships. Similarly, the environment receives and codes
information from the individual regarding his/her physical
and mental state. From this process of information exchange,
the systems move to response actions. Response itself pro-
duces a new set of stimuli (Laszlo, 1960).

Throughout the exchange process of receiving, coding,
and responding to stimuli, man/environment transactions are
driven toward a state of dynamic equilibrium if successful
adaptation is to occur. Positive adaptation of the indi-
vidual to the institution would be developed when the energy
flow from the environment is in equilibrium with the indi—
vidual's ability to detect, code, and respond to it (2181»
congruency). Figure 2a indicates thigflideal.traesaeeienal~~

__ _ MW-

prgffss;fl#But other modes of adaptation are possible when
the transactional process is discordant and linkages either
are not established or information is distorted. Figure 2b
depicts a man/environment transactional process where the

energy flow from the environment is too forceful when im-
M ____-___.__._

 

 

pinging on the individual's ability to receive it or code

 

vidual and the feedback response is haphazard and discordant

with the environmental code. Furthermore, feedforward is

21

virtually halted. In the institutional environment this pro-
cess occurs when stimulation of the individual is too strong
for the capacity of the physical, mental, and emotional ener-
gy stores to handle. Confusion, disorientation, and 'senile'
responses are the inevitable result. Conversely, a recipro-
cal process may occur in which the individual overwhelms

the environmental energy flow. In this situation (Figure
2c), the individual's capacity is greater than environmental
stimulation and could result in monotony and boredom for the

__ ____.__——-—-'“ 44....__-__.._~ I ..

individual. Continuation of such a transactional process

L...“

would lead to either overdependency or escape through fan-

tasy. In either case, communication is again distorted or

a) Dynamic Equilibrium E: ;’

lost.

w
b) Low Capacity Individual E
c) High Capacity Individual E: ;,
1 A

 

Figure 2: Man/Environment Communication Exchange
(After DeLong, 1974)
Thus, it may be inferred that the two primary mechan-
isms at work in the interaction of individual in the insti-

tution are the organization of environmental stimuli to

22

communicate informational content and the individual's
capacity to perceive and code the stimuli. An analysis of
these mechanisms relies on information obtained from environ-
mental research, communication systems theory, and geria-

tric research.

Communication: Content and Code

 

As stated, congruence in man/environment interactions
involves an equilibrium between the energy flow from the
environment and the processing capacities of the individual.
In studying man/environment congruence in the physical realm,
Leon Pastalan of the University of Michigan Geriatric Insti-
tute has conducted a considerable amount of design related
research for the elderly. Pastalan's thesis is that ef-
fectively programmed environmental stimuli will enhance the
individual's capacities. From his work, Pastalan reports

that two basic principles have emerged:

a) organized space as stimulus (e.g., environmental
communication)
b) organized space as orientation (e.g., cue to the

behavior setting) (Pastalan, 1971)

Regarding space as stimulus, Pastalan states "the
environment is organized as intricately and systematically
as any spoken language" (ibid., p. 8). The communication
transmitted from the environment to the individual involves
the cueing of the individual as to the appropriate response

to the specific situation. Just as Perin (1970) has stated

23

that the environment responds to the stimulus of human
needs, Pastalan states that it does so with information-
laden cues. The second principle to emerge from this work,
organized space as orientation, deals with the design con-
cept of manipulating spaces to communicate a singular, un-
ambiguous definition of the space and its relevance to human
activities. He is referring generally to the same concept
as Barker's Behavior Setting. Barker (1963) contends that
the milieu is a composite of time-space-object which serves
as the generic place for human standing behavior patterns
(g;g;, systematically recurring episodes of human activity).
In other words, orientation to the behavior setting requires
the organization of stimuli into recognizable patterns for
shared identification of space as 'place' for individual or
group actions. Thus, material resources cue informational

exchange. Orientational cues provide three levels of infor-

 

 

ation that enable behavior setting identification:

 

x

l) Orientation involves the individual's ability to

comprehend the physical form and boundaries of the
M» M ,,,,,, __.__._— fl

 

environment The confi uration of h sical re-
‘\~111_ g P Y

/

sources provides the individual with information
about the location and attributes of mass and
void and defines locus, scale, and directionality

for human movement. b (3

.g 34 t

2) Orientation involves the individual's ability to» ~‘7
/ 1/

\\i tif ‘meaningful information amid a myriad of

stimuli impinging on the sensory system. It

24

allows discrimination of information relevant to

A

 

needs and behaviors from meaningless cues. It
provides a hierarghyfiof focal points relative to
:~«11_
behavior in the milieu.
3) Orientation involves the individual's ability to

sen e the congruency between environment and behav-
________.......-.-.-._,__..— WW

ior. By definition, the behavior setting implies

 

.._../

’ iy---

that place and behavior possess a synomorphic
relationship. The environment cues the individual
to appropriate behavior in the place, and con-
versely, the appropriate place for behavior. Fail-
ure to achieve sensed congruency could result in
some form of disequilibrium.
Relating these concepts to the ecological framework that
initiated this chapter, it may be inferred that Pastalan's
principles of organized space as stimulus and orientation
correspond directly to the individual's detection, percep-
tion, and coding mechanisms in the man/environment inter-
face. Thus, it is the establishment of a communicational
linkage at interface that allows exchange of orientational
cues.

Alton J. DeLong (1972) has developed a comprehensive
study of man/environment communication systems. He assumes
basically that the environment constitutes a system that is
learned and shared socially. Internalization of the en-
vironmental language enables orientation to the behavior

setting and recognition of socially acceptable, adaptive

25

behaviors. Any communication system is composed of two
primary elements: form and content. Content is the informa-
tion that is passing through the system (2181» orientation),
while form is the physical, formal property or structure of
the expression (21812 stimuli). Time, space, and culture
determine the form and content of the message. Participation
in a communication system implies several things. First of
all, it delineates group membership. In order to belong to
a group, one must be able to receive and transmit its com—
munication. The codes and signals must be understood in
both form and content. While in person/person communica—
tions, one's ability to manipulate codes will determine his
position in the society, in man/environment communication
code mastery will determine one's ability to orient and
manipulate the physical environment. Secondly, degree of
participation depends upon the person's ability to encode

the environmental signals. Child development theorists hold
that these abilities are developed as a direct function of
physical and mental maturity and require maximum use of one's
faculties (Piaget and Inhelder, 1956). Finally, participa-
tion implies that if the envrionmental signals are suffi-
ciently internalized, "the organism has transformed the
environment into something predictable and redundant"
(DeLong, 1972, p. 276). Furthermore, internalization implies
that while behavior is reliant on signal usage, the signal
itself or its meaning may be intangible to the individual.

Therefore, resultant behavior may be difficult to associate

26

with specific signals. Nevertheless, internalization and
transformation of environmental communication allows the
person to orient to the physical milieu in order to accom-
plish his goals. These aspects of participation will be
further analyzed as they pertain to the elderly individual
in the institutional environment upon further development
of DeLong's theory.

With environment being characterized as the entire
milieu impinging on the organism, one organizes that milieu
by the coding process of receiving stimuli, analyzing con-
tent, and storing the information for future reference
(DeLong, 1972, Laszlo, 1960, Struder, 1976). Psychophysical
research indicates that this is accompanied by feature de-
tection and analysis (see Chapter 3). According to DeLong,
the process of coding in the man/environment relationship
involves three aspects. The first is the perception that the
apparently discontinuous milieu of stimulation can be char-
acterized as continuous, regular, and redundant. The organ-
ism detects and orients the stimuli. This aspect is labelled
ETICS after Pike (1967) who coined the term from phonetics
to describe the study of behavior from outside of the system.
The second step in the coding process is EMICS, from phon-
emics, or studying behavior from inside the system. This
involves the grouping of stimuli into discrete units, there-
by increasing code redundancy. Finally, EMICS are further
organized to provide specific combinations of stimuli by

which the organism can control the flow of information in

27

in the system. Figure 3 indicates the development of these

concepts.

x23, 0380 xx 00

:3 jx () )( )()( XD( CH3
0 0X xxx xx 00
ETICS EMICS TACTICS

Figure 3: The Coding Process (after DeLong, 1972)

Implications of the coding process are complexity re-
duction, constancy, variability, and change. Codes reduce
complexity in the environment by relying on classification
and redundancy. In the EMICS process, complex stimuli are
ordered into classes with a single-featured characteristic.
TACTICS further reduce complexity by limiting the possible
combinations of EMICS that will be regarded as necessary and
‘meaningful. Furthermore, complexity reduction allows the
organism to maximize contrast between stimuli, thus, en-
hancing figure-ground relationships. The second implication
of the coding process involves the concept of constancy,
which allows for a certain degree of predictability in the
environment. While the environment is in constant flux, it
does retain a certain degree of constancy. "An organism
could not tolerate a different Universe every moment of its
existence. It would suffer information overload. Predicta-
bility in the environment implies regularity, a degree of

constancy despite inherent environmental variability"

28

(DeLong, 1970, p. 357). Constancy is achieved by selective
desensitization to many aspects of the stimuli by genetic-
ally and culturally controlling the EMIC and TACTIC combina-
tions. Although uniformity in the environment is a neces-
sary condition for human participation in the communication
exchange, the code must also allow for variation and change
concomitant with human development. Variability delimits
the range over which the codes are differentiated from one
another, and allows the individual to ignore irrelevant
information. The final implication of the coding system,
change, allows the reorganization of TACTICS to enhance con-
gruency between environment and human activities. Thus,
the coding process allows the three levels of orientation to
be comprehended by the individual; spatial form and boundar-
ies are identified, focal points established, and behavior
settings comprehended. DeLong concludes that,
Codes...give every appearance of having evolved pre-
cisely to regulate the fine balance between relative
simplicity, or redundancy and relative complexity, or
information...the code represents the amount of com-
plexity that can be reliably handled without intoler-
able error in performance. (DeLong, 1972, p. 643)

Thus far, this discussion has relied on a pair of
assumptions which are that environmental messages are trans-
duced by the human sensory system and transmitted to the
brain for coding and that this process is accomplished by
all persons. Both of these assumptions have grave conse-

quences for the elderly person attempting to code the insti—

tutional environment. Successful coding depends upon the

29

intellectual and physical capacities of the human system
(g;g;, acuity of the transduction system). Studies dealing
with the intelligence of the elderly cohort indicate that,
in general, they demonstrate poorer performance than younger
subjects in concept attainment, problem solving, learning, and
memory (Schaie and Gribbon, 1975). Other investigators con-
tend that intelligence pg; s3 may not diminish with age, but
rather, certain intervening variables may have a stronger
effect on information processing abilities (Wallace, 1956).
In a series of studies on information processing of complex
stimuli presented serially, Wallace concluded that slower
response times in the elderly subjects could be explained by
physiological decline at the sensory level and along the
neural network, rigidity of set (TACTICS) precluding recog-
nition of variability, and a general lack of confidence
among the subjects. Similar conclusions have been drawn by
other investigators (Birren, 1964, Geist, 1968, and Surwillo,
1973).

Although further study of age-related information pro-
cessing speed and accuracy is needed, considerable research

\W
already has been done to characterize the decline of sensory

functioning concomitant with aging. Ch42335/5‘disQEEEEE‘EEi§fl_~
'work relative to the human visual system. While there is
sufficient information available to stimulate conjecture, it
should be noted that the precise relationship between sen-

sory function and human behavior has yet to be established.

Furthermore, the human system is capable of adapting to

30

varying ranges of sensory deprivation through time. As sen-
soryfidEgradgtign_in_Ehg_gldgr1y is usually a gradual pro-
cess, the individual may have adapted to decreasing informa—
tion flow by learning to perceive the message with very
little redundancy or by relying on other sensory modalities
to supply the missing information. Nevertheless, to study
the man/environment coding process, a knowledge of sensory
functioning is necessary and further research is needed to
identify the nature of the loss and its effect on information
processing. In summary, however, it may be generalized that
the sensory sensitivity of the older person is diminished,
and that the time required for processing and reacting to en—
vironmental cues has increased. These liabilities in coding
ability, coupled with other aspects of the loss of control,
characterize a group of individuals who may experience diffi-
culty in participating in man/environment information ex-
change.

As stated, participation in a communication system
implies that one is able to receive and transmit signals de-
lineating group membership and to orient to the behavior
setting. Failure to adequately internalize the information-
al code could lead to haphazard responses in orienting to
other memberscflFthe group, activities, and places. Both
stability and variability in the environmental code are per-
ceived as irrelevant to behavior. The individual may wander,
disengage, or ritualize behaviors. Human response to the

institutional environment has been studied by several

31

geriatric researchers. Sommer and Ross (Sommer, 1970) re-
port that the simple rearrangement of furnishings in a day-
room resulted in confusion, disorientation, and distress
among the subjects. It may be inferred that the subjects
had ritualized response to environmental signals to such an
extent that variability destroyed their coding. Other in-
vestigations have expanded on this concept to examine the
behavioral effects of diminished man/environment information
exchange by studying social interaction and self-perception.
In the Sommer EE,§l study, the researchers' organization of
the furnishings introduced greater redundancy into the behav-
ior setting code. Results indicated that the subjects were
eventually able to internalize the new TACTICS, and social
interaction increased significantly. Social interaction was
also studied by Snyder (1973) in three New York nursing homes.
After observing social interaction on three levels -- con-
gregation, brief interaction, and conversation -- Snyder
found that the significant variables affecting interaction
included the location and attributes of the space, traffic
pathways, and furniture arrangement. Lawton's (1973) study
of 12 housing sites indicated that the behavior of older
people was affected by the location and type of environment
they were in (g;g;, behavior setting). Lawton and Simon
(1968) compared deliberate transversal of space for social
interaction to reliance on passive encounters. They con-
cluded that the intervening variable affecting choice was

docility of the residents resulting from decreased competency

32

levels. This may be related to lowered coding capacity. To
date, however, there has been no serious attempt to analyze
this relationship.

For the designer of institutions, as provider of the
environmental stimuli, this represents a serious gap in
information required for appropriate design. A major ques-
tion remains unanswered: How may environmental stimuli be
organized to facilitate coding mechanisms for orientation to
the behavior setting? In order to better understand the
parameters of this question, a series of other questions
bear investigation:

- What are the physical parameters of stimuli that

indicate redundancy?

- What parameters of redundancy mark insufficient cue-

ing (understimulation)or excessive cueing (noise)?

- What are the preferred stimuli for orientational

coding?

- Do orientational cues possess a hierarchial order?
Wfl< ' \1W

 

— Can the environmental stimuli be simultaneously con-
gruent with both the low competence and high compe-

tence individuals?

Conclusion

 

The objective of this chapter has been to develop a
theoretical framework of the man/environment communication
process and to establish a potential area for future design
related research for congruence enhancement. While DeLong

and others have provided an intersting analysis of the

33

communication process, there still exists a definite gap be-
tween thepryfland pragtigal,appligation. The designer has not
been given the necessary information for implementing a
coding system in the environment. Geriatric research, on

the other hand, has attempted to deduce from data on exist-
ing environments the effect of codes on the individual. There
does not exist at this time a bridge of research that devel-
ops a code and analyzes the coding process. It appears that
the major stumbling blocks to developing such research lie

in the inability of practitioners to adequately define, clar-
ify, and operationalize such concepts as stimuli, orienta-
tion, code, and energy transfer. Thus, we do not know
whether or not the coding process, as theoretically outlined,
actually occurs in the human adaptation process to the envir-

onment. It appears plausible, but until researchable hypo-

theses are generated, the gap will remain.

CHAPTER 3: COLOR AS AN ORIENTATIONAL CUE

Introduction

 

Color in the physical environment involves the complex
interaction of technology, artistry, and human perception.
Information from a variety of disciplines enables the design-
er to employ color as a resource for optimal behavior set-
ting performance. Physics defines and measures the inter-
action of light and color to allow for intended visibility
and color rendition. Chemistry standardizes pigmentation and
color identification. Art provides harmonious color patr~
terns. Physiology describes the sensory stimulation of color
and the related physiological responses. And psychology pro-
vides predictions of the behavioral response to colored en—
vironments. Ignorance of any aspect of color may result in
nonfunctional design.

In Chapter 2, design of the behavior setting has been

described as the manipulation of physical resources to com-

_w—_._—-h ,
_—-—-—' -

 

 

rue-Wflr ‘W

municate informational ues in response to human needs.

r*" ‘wher—

Moreover, it has been established that humans relate to their

 

environment only to the degree that it contains information
relevant to them. Thus, coding the prosthetic environment
requires the manipulation of color relative to geriatric
needs to ensure perception and identification of the behav-
ior setting. This suggests that color may be treated as
both an independent variable influencing environmental per-

ception, and as a dependent variable being affected by the

34

_.,.—— ,,

35

organism's ability to detect stimulation. The objective of
this chapter is to study the informational character of color

in general, and specifically, color as an orientational cue.

Color and Communication

 

Color communicates environmental information to the
human organism on several levels: physiological, psycho-
logical, and cognitive. Perception and response to such
communication may be categorized as unconditioned, condi-
tioned, and reinforced. Unconditioned perception involves
the physiological response of the organism to a color stimu-
lus. Within the visual apparatus, perception initiates with
absorption and transformation of light energy into an electro-
chemical impulse and culminates in stimulus detection. This
process is discussed in Chapter 4. Malfunction of the visual
system inhibits or diminishes the individual's ability to
perceive environmental information. Blindness, color blind-
ness, and the developmental level of the individual all
affect ability. In blindness, the organism is insensitive to
all radiated and reflected light. Color blindness involves
varying degrees of insensitivity to wavelength differences
resulting in color confusion. And finally, physiological
development of the organism affects color perception. Chap-
ter 5 deals with color vision tests that indicate that color
sensitivity increases up to age 20 and diminishes after age
30 (Lakowski, 1969). Moreover, since the visual apparatus

can process only a limited amount of spatially or temporally

36

contiguous data, false perception, or illusion, may occur.
Phenomena such as afterimage or subjective color perception
are related to the system's information processing ability
and result in an unconditioned response incongruent with
true environmental information.

Beyond visual perception, the human organism also ex-
periences other unconditioned responses to the colored en-
vironment. As early as 1938, Podolasky summarized available
research linking colored lights with respiratory, muscular,
and psychomotor responses. More recently, Gerard (1958) des-
cribes a series of experiments studying normal adult response
to colored lights. Test results indicate that red and blue
lights produced differential effects on blood pressure, res-
piration rate, eyeblink frequency, palmar conductance, and
cortical activity. Norse and Welch (1971) found varying
galvanic skin response to violet and green lights. Although
these tests do not offer conclusive results, they do tend to
support the proposition that colored environments affect the
autonomic functions of the human organism.

The second level of human response to color deals with
conditioned perception, or the associative aspects of psycho-
physical response to colored stimuli. The term conditioned
is employed as it implies the developed ability to cogni—
tively associate color with size, weight, depth, and tempera-
ture. Although studies employing color as an independent
variable have often yielded contradictory results, the evi-

dence is strong that color does ellicit a conditioned

\\\_/'

 

37

response. The major difficulty in early research appears

to be the inability of the test to differentiate the dimen-
sion of color (hue, luminance, and saggration)-actually
affecting perception. Nevertheless, in his summary and
analysis of current work, C. Payne (1964) found that in gen-
eral, luminance appeared to be the major cue to size, dis-
tance, and apparent weight, while hue cued thermal percep-
tion. He concluded that future laboratory study of color as
a cueing mechanism deserved greater study particularly re-
garding the interactions of gradients of the color dimen-
sions. Some work in this area has been done and will be dis-
cussed later.

How color has come to cue has also been a controversial
topic in recent years. Are conditioned responses (218;: red
associated with fire, and blue with ice) inherent in the
human psyche or are they more closely aligned with rein-
forced response (g;g;, culturally shared)? Morgon, Goodson,
and Jones (1975) studied the correlation of age to the con-
ventional responses of red/hot, yellow/warm, green/cool, and
blue/cold. Although 18-year-old subjects showed significant
tendencies to these associations, the lZ-year-olds only
agreed with red/hot, and the 6-year-olds showed no associa-
tions beyond mere chance. Future work in this area probably
will be directed toward a greater understanding of the psycho-
physical and cognitive foundations of conditioned response.

The final level of human response to color communica-

tion, reinforced perception, involves the integration of

38

unconditioned and conditioned responses with cognitive,
emotional, and cultural variables. It is the realm of sym-
bolic or affective meaning of color and color preferences.
While this level affects the intimate informational charac-
ter in man/environment interaction, it remains the least
understood because of the multitude of variables associated
with it. To date, the bulk of experimentation related to
reinforced perception has yielded inconclusive results and
highly intuitive generalizations. Schaie and Hess (1963)
have described early work that led to generalizations such
as red is exciting, passionate, aggressive, yellow is vital,
energizing, blue is restive, calm, and so on. These early
works, however, were characterized by grossly oversimplified
technique leading to unidimensional characterization. For
example, the technique employed by the often referenced
Wells' (1910) study involved placing a color chart of 12
hues (full saturation) before a group of students. A series
of words (2181» quiet, sad, lively) were written on the
blackboard, and the subjects were asked to place the hue
number next to the word they felt best described it. Re-
sponses were simply tabulated and presented.

The introduction of the Osgood Semantic Differential
(S.D.) has provided a more sensitive instrument for measur—
ing affective meaning. The S.D. is based on a three dimen-
sional 'semantic space' employing sets of bipolar adjective
scales. The subject is presented a color stimulus and rates

his/her response on a seven-point scale (e.g., good----Fbad).

39

Factor analysis of the scales yields concept clusters that
describe a single dimension of affective meaning subject to
statistical analysis. The S.D. has been employed success-
fully in several studies in recent years. They have shown
distinctive affective connotations related to hue, value, and
saturation with both colored surfaces and full-scale environ-
ments. The results of some of these studies are discussed
later in this chapter.

The value of generalizing about color preferences is
questionable. Nevertheless, it is an element of response as
it affects the liking/disliking of an environment. Color
preference studies are numerous and it remains the unique
area of color psychology that has employed elderly subjects.
Katz (1931) found a positive correlation between preference
for long wavelength colors and length of institutional
tenure using elderly psychiatric patients. A comparable
study (Mather, Stare, and Brienin, 1975) yielded contra-
dictory results. Of the 102 subjects tested (65 female,

37 male) the majority preferred blue. Males preferred red
second, green third, and yellow last. Females chose green
second, followed by red and yellow.

In summary, a broad range of psycho-physical research
supports the proposition that color in the environment stim-
ulates human response on a variety of levels. The questions
of how and to what extent color communicates environmental
information remain unanswered. Nevertheless, with theC4rfi/I

x\\_fiflI____”_,1__1,~_1\_f_1_1_1
research base currently available, it is possible to deduce

40

that color can and does serve as an orientational cue in

the behavior setting.

Color as a Cue to Orientation

 

It has been established that orientagign iELEEELEEEQV’

W—

 

 

fior setting involves the user' s ability to comprehend the

4¢<7/generalgspatial boundafI;;)andzf§E§:hf\§h§~g§yirggz:nE’#to

identify meaningful information, and to sense the congruency

 

of space and activity. The use of color, then, must neces-

sarily address all of these aspects in order to serve as an
— “hf”

 

orientational cue. This is particularly true if the design-
er/encoder intends to provide an environment compensating for

the elderly individual's loss of control. To date, there is

M

 

 

 

_no available research providing a comprehensive study of

color as an orientational cue, but the summation of a variety

 

of work supports the general hypothesis that color does

serve as a cue to orientation in the physical environment.

Color as a Cue to Spatial Form

TIN 4
The basic processes of formIand space_perception lie
. , k_ ,/

K.”

1n the detect1on of contrast and contour, also integral

parts of color perception. Contrast inyplyesmthe system‘s
ability to detect differenggs~in_thgpgptig§lwarray. For
example, the outlines of a room, objects, light, and shadows
provide differential stimulation of the visual system. But
the optical array projected on the retina is a two-dimen-

sional image of a three-dimensionalgwgrlde_.Therefore, while
N ~1__-.. MM

difference detection is simple in theory, it involves the

41

complex interplay of thétaho§133§é§, andxlight detectian.
This interplay allows the observer to comprehend not only
the difference between white object and blue background, but
also that the background remains constant in hue as it turns
a corner and that a bright spot is a patch of sunlight, not
an object.

Constancy refers to the phenomenon that a colored sur-

face is perceived as uniform in;EE§ and lightness independent
1.. ._*_______ _-

-_ awa—

f-” ss-u-r

of illuminationgmeor example, a piece of paper is perceived
as white and a lump of coal as black regardless of illumina-
tion level. Furthermore, even when crumpled, the paper re-
mains white and the contrasts are perceived as shadows.
Without the constancy principle, any change in illumination
or viewing angle would disallow stability in the environment.

-has been shown to be linked to a figure/ground

rEIaEiafiship (Kauffman, 1977). So too has a second pheno—
menon,(EEEEEEEEEEE;:E§£EEEEEJ In this instance, two figures
of equal reflectance will appear unequal when the grounds
are different (2181: red appears more orange on a blue ground
and more purple on a yellow ground).

Questions on both constancy and simultaneous contrast

have led researchers to place greater emphasis on the role

-fl...“ 1-,
.A‘W “Huh-“- 4.-

1..

of edge informatiofl in color and form.perception. This

\I ,— H M” \m tum AW
movement has paralleled psycho-physical research in feature
detection and cortical activity. Experimentation on edge
perception in these areas has revealed the importance of

edge information for the comprehension of visual space.

42

But first the work of E. Land (1977) and A. Gilchrist (1978)
in color perception should be examined as it indicates the

importance of edge in color detection. Land's early experi-
g‘______fl__,_1

 

 

~—EEEHE;—dealt with black and white photographs of a scene

taken through red and blue-green filters. A red object would
show up as very light through the red filter, but almost
black through the blue-green filter. When the two images
were projected onto a screen again through their respective
filters, the composite scene was revealed in full color.
He then postulated that the visual system could contain

‘V*I\ ,1 three retinex systems, sensitive to long, middle, and short

R-

, giI)
yéfi// " wavelengths, that would integrate color perception based

 

on lightness comparisons as in the photographs. 5T0 test

this hypothesis he developed the<§§§§£§§£>experiments in
flfi___~_____’/,_LI

which the visual scene contained patches of color similar to
W V ‘

 

 

 

the namesake's paintin 3. His tests indicate that each

 

\_—-—J
“retinex system measures reflected light E912£Ihzxggigfi,as

Q\ 1t scans the field. Measurements of closely spaced pairs

(IC'E \ are converted to a ratio and subject to a threshold test.

 

 

 

 

TTU’ If the ratio does not vary from unity, it is judged as con-
L”J stancy; while variation is deemed a change. Integration of
‘m__~flfl,,11

the three retinex systems provides the sensation of color.

 

Although such point by point measurement sounds a tedious

task, it is readily linked to the saccadic. movements of the
I eye. The eye scans a surface with flickering tremors with a
.\\\“
frequency of 30—150 cycles per second. Krauskopf has shown

that these tremors cause a constant relative displacement

43

CKJ’Pf the retinal image resulting in edge detection and color
é;k perception (Gilchrist, 1978). The Land system holds under
T‘*~*~—-m—-11_1_-M
uniform, graded, and colored illumination, but Gilchrist

—.——.-..

contends that it break5"dbfifimfinder“nonuniform“iiiumination,

 

 

such as the corner of a room. He has proposed that color

perCEEEion is inexorably linked to depth perception and that

 

 

color detection is based on the visual systemis ability to
discriminate illumination edges (£181: planar change and
shadow) from reflectance edges (2181» color). Although his
work using miniature rooms is still in the early stages,
evidence indicates that the visual system contains parallel
detection mechanisms for both illumination and color, but
both based on edge perception. These conclusions readily

41\\\ .
relate to<§6hstanfy>and<EEHETEEE>phenomena but now 1nclude
pgg/ .\V*#,

the important pfinciple of edge detection.

 

W
Psycho-physical studies of form perception also em-

 

fi_',,._1
phasize the role of edge perception. D. Hebb's theory of

m
"a” A_‘

 

feature detection notes that observers analyze a form

’4- "W
-._.

 

through fixation on the composite lines and angles rather

than the figure in_toto as the Gestaltists claim (Kauffman,
, "’T ' “W \W’

1977). Repeated exposures to the stimulus lead to cell

 

assemblies in the brain sensitive to that feature. Cell
assemblies then fire in phase sequence that reveal the form
(g;g;, three angular cell assemblies fire sequentially to
indicate a triangle). Furthermore, Harris and Gibson

/:E;%§;/I(Kauffman, 1977) have surmissed thatflEheisameifgatu£g_§gtgg;_w

{Eblor information. Thus,

~— .— -..._ __ ._ __ _-

  

P tion channels carry both/edge nd

r-_.._ ~~_.— -__..
/

k

 

44

a psycho-physical link can be established between the detec-
tion of color and the perception of form. To date, the
scant experimentation in this area has been limited to

single features (e.g., one-hue line gratings), but the route

for future research using complex scenes is evident.

c HHA'FC—I-w—“r—fi
-— ..

1"" ‘-—..__

Color as a Cue to Meaningful Informafibn\

/////, Color codes can provide specific information in the

 

{ env1ronment by establishing a sense of direction and focal

I points. Evidence to this fact comes from data display ex-

p.._— v

perimentation on visual search tasks requiring rapid and
_/,1___1_1,¢—

precise identification of target information. Search type
- - _‘hw -‘-'

tasks are important because they require the observer to

 

 

discriminate meaningful targets from visual clutter. In frf£”“$‘

.L/ i” (1,. .4.
. / A: \t N ‘
such tasks, color as a component 1n a .edundan- code has

-11 coicIeJ’

”I,

\-

repeatedly aided in decreasing target identification time.
#J‘.___,__111

Erickson (1953) found that using a multi-dimensional code

  

/' A "
’A- OJ 3 I . .
.6 I} , .
v f .

(hue-size-brightness-form) in 6§§,'£héoo, andrffifir:iéy>com_

4 binations, the inclusion of hue consistently decreased
4 " \/—\_____'

.1
0’ ‘

147/ search time. Moreover, hue, hue- orm, and hue-form-bright-

~..
mm

 

 

ness codes decreased search time more than the four-dimen-
sional code. This could be related to the shared channel
concept of feature detection. The findings of Promisel
(1961) reinforce this assumption. They indicate that a tar-

get defined by hue-form was the most readily identifiable

/
1,/

from visual clutter including objects of the target'sIhue‘“w

or’fb , but not both.

Several factors influence the reliability of a color

45

code. The first is that of<hé§2§2mbg;4 While data vary,

they generally indicate that the ngrmal_9bsfrver can absg:

 

 

lutelygidentify only \in hues (Jon s, 1962). Secondly,

 

(iabackground contrast affects code legibility. Hurvich and

 

Jameson (1959) have found that targets of low saturation
WM

and/or brightness compared with the background produce

adverse effects. Gustafson (1960) suggests that figure]

ground brightness contrast should be at least 75% to keep

(9)

Third, stimulus size
(I... ‘N

must increase with distance to minimize the effects of color

discrimination errors to less than 1%.

 

 

 

 

distortion caused by chromatia abberation. Conover and
,.. w I

Kraft (Jones, 1962) indicatggthat the stimulus must subtend
a visual angle of at least 20' for the code to be reliable.
Andafinally, illumination level affects the use of a color
codeTT’J;;;;N(I9627summary of available data concludes that
mid-spectrum hues provide greatest reliability under low
illumination; blues, greens, and reds being more variable.

In the physical environment color codes may be employed

,4

fo focal point emphasis just as those used in visual search

\

tion of hazardous eas or materials and as a directional cue.

Furthermore, it may be assumed that a color code used in

gtasks. This can be shown to work effectively for identifica-

combination with affective meanings of color may provide a
[7 focal point for behavior setting ident’fication. There is
K to date, however, no experimental evidence to support this

assumption.

{’Ii 46

JIM Io!»

A sense of congruency between behavior setting and

Color as a Cue to Congruency

activity extend beyond rec0gnition of form and focal point
w

to the affective meanings the environment(§£:EEEEE:) Studies

repeatedl indicate that color in the environment can and
does<eIII:;;?such connotations for the user. Using the

Semantic Differential, Wright and Rainwater (1962) tested

the meanings of color to 3660 low income subjects. Factor

 

analysis of the scales yielded five distinct concepts: hap-
piness, showiness, strength, elegance, and warmth. Their
results indigaggd linear EQEEEIEEEEEEIEEEYIEE. alue3~satura-
/tid;? and COIZr‘conhotat1ons; As a similar relationship

did not emergewfor‘hue, they contended that hue must fall
into a periodic type model of connotation.

The extensive research into color meanings conducted
at the Swedish Color Center at thesburg has resolved this
problem somewhat. This work has centered around the use of
the Natural Color System originally developed by Tryggve

vf—r—
Johanssen and based on Hering's onent Mechanism Theory

 

(Chapter 4). In the Swedish color system hue is used to

denote the color' 3 similarity to two of the four psycholog-

M‘ww

 

m~w_
‘--—v

 

—"’ WWFr-H

ical prumaries (__g;, redness, blueness, yellowness, green-
ness). Chromaticness is comparable to saturation, and

brightness refers to the apparent whiteness or blackness of
the color. From this framework, a color solid is developed

similar in appearance to the Ostwald system. Using the S.D.

format, various experiments into the meaning of color have

47

been conducted. Correlations achieved in factor analysis
of test results are mapped onto the color solid. Isosemantic
mapping yields a comprehensive model of color connotation

along the three dimensions of color simultaneously.

/A <2:E§EE§;;;EZ—;;;E2§g>has been employed by Acking and

Kuller mm to tudvW

; Using a perspective drawing of a furnished room, they pre—

 

sented the subjects with 89 color combinations to judge.
M J1

 

 

Factor analysis yielded five dimensions of meaning: open-

“a

ness, complexity,,social evaluation, potency, and pleasant-

,;2:%> ness. Openness was defined as the apparent spaciousness of

   
 

 

.5”

 

——__

the room. They found a positive correlation (r = .76) be-

 

 

V

elation with furnishings, but not walls, which they attri-
M

buted to a contrast effect. Nevertheless, chromatic strength

, ‘ Jr A r’""‘” ‘ “FM
\\ IV' tweenfopennegs and lightnessn Chromaticness also had a cor-
1?

 

had a high correlation (r = .81) to judged complexity. In

’fit‘“.— on“-

‘\\\ :—
general, weak colors were calmingp and gtrong excitin re-
K‘V‘ -'

A
‘ _—

 

 

#‘_-

 

 

gardless of hue. Thus, a strong green was equally exciting
as a strong red; a qEEEBEEfdfggggigigEEEEMQf existing psycho-
; physical.studies;d Color blackness was correlated to both
i potency (r = .65) and social evaluation (r = .72). There

I

1

i were no appreciable correlations between color and the
I ”‘f—‘f

l

w—

 

 

\ pleasantness factor indicating that color preferences may
. \ - , __r-_._,_ 1w“?
£Zi> be maintained:within hues rather than/betwee hues. While
.V ; J ‘—

these results are far from conclusive, they do indicate
that the affective meanings of color may be manipulated in

order to induce a sense of congruency between the physical

48

environment and the human activities therein. Furthermore,
it could be deduced that intended environmental congruency
could be achieved even for users with_vi§ual handicaps such

as color blindness or developmental insensitivity if all
W

three dimensions of color are considered. This could be
NM” ‘ “N..."Uw '7‘

particularly important for the elderly experiencing visual

 

M...“ put—Mi— "——

-—-‘ “—I- 1.'_.- n.

degeneration.

Color in the Geriatric Institution

 

   

The use of color as an orientational cue in institu-
lL///ti;ns for the elderly has been promoted by geriatric re-
searchers (Lindsley, 1969). Drawing from ophthalomological

data that identifies the geriatric visual system as degen-

 

—-‘ ~_.—~

erate, resulting in diminished ii sual acuityy<brightne§sl
. m , ,——

*M

       

t wavelength detectio environmental designers

 

have generated highly prescriptive methods for\3§ing/gglgr.

as an aesthetic element and as am It may be
V /

summarized by the rubric, "use bright, warm.colors of high
contrast to designate specified areas". This type of gener—
alization may lead to considerable problems. For example,
Marcella Graham (1976) describes her experience in such an
environment.

Shortly after entering, I began to feel assaulted by
red, orange, and design. It was necessary for me to
wait in this area for approximately 25 minutes....It
» was the longest 25 minutes of my life. Interior de-
ifi? signers had been retained to make the place cheery,
so they enveloped the area -- approximately 40 feet
by 24 feet -- in total and unrelenting color. While
it was a positive statement by the designers, it was not

in any sense of the word a therapeutic environment.
(Graham, 1978, p. 11)

49

Similarly, Pastalan reports that contour boundaries

were difficult to distinguish when bright, high contrast

colors were employed, "because the intensity of the colors

seem to overlap and as one focuses on the boundary it appears

to shift" (Pastalan, 1974, p. 6). Clearly, the use of color

1_______________'
,M,J;§£{ as a t1mulusIdeservg§£g£ggggg:sc;utiEZ)in order to answer
W’-
2 the

‘basigagugstion -- how may color be used in the geriatric
W_

 

 

institution to enhance effectance in behavior setting identi-
W~“' “MW-“~r —-»- ..—.— --—~... -. a.“ Mr“... ,_ _____~ _._._- __l__'_~_»_n_. -....._ ._..._... ..-—-
fication?

W
To date, the only research dealing with geriatric

 

effectance demands on the environment has been conducted at

the Geriatric Institute at the University of Michigan --

Wayne State under the direction of Leon Pastalan. Wearing

the

   

.spectacles that simulate age related visual defects,
W_ V M
subjects engage in daily activities noting problems encount-

ered. Results indicate significant problems inifllflflIF

i “v ‘

f ‘\

J \brightness, nd edgéldetection. From these initial findings
...4;N~“flffl,,___ii

1
1t is ev1dent that cons1derab1e research 13 necessary in

 

 

 

order to successfully employ color as an orientational cue.
Furthermore, there is no available research dealing with the

5 affective meanings of color to the elderly. Therefore, future

work using elderly subjects, should be directed at an in-

; depth study of the following questions:
1 - What are the competencies/incompetencies of the
elderly in detecting color cues?

- What dimension(s) of color provide the greatest

amount of information for the elderly?

50

- What are the physical parameters of color cues that

mark nsufficient cueing (understimulation) or ex-

cessive cueing (visual clutter)?

 

- What are the affective meanings of color in the en-

vironment to the elderly?

Conclusion

 

The objective of this chapter has been to study color
as an informational resource in the environment and to de-
termine whether it may serve as an orientational cue for the
geriatric user. Although an impressive amount of research

does indicate that color stimuli do carry information, the

 

meanings of that information remain controversial. Fur-
My.” 111.11.-.. .. A , _ - W...“

thermore, we do not knowkho

-n..._ _‘1_ kfikd“

 

       

 

r; ‘-.__- ..“..o-—""" 4...‘

an emotive aspects of the hu-

.-

      

6.989.319.1176 .

 

 

 

-- -.-

K...

 

 

     

man ystem. .
._\ /—————-—’/
.1111 _'”’,H_W

Given the parameters of an orientational cue, evidence
from the literature indicates that color may provide this
information. The research base, however, is very diverse
and quite unrelated. This paper is the first attempt to
establish such a connection to date. This may be because
much of the research cited herein is quite recent and still
subject to much controversy. Nevertheless, it appears

plausible to assume that color does serve as an orientation-

   
 
  

1 cue. It is obvious, however, that mfgexkngwledge of g,

olor's role in feature detection is inade uate information
W v

 

 

he designer. We simply do not know how color and edge

perception may be applied to the environment to fit user

51

requirements. Regarding color as a:£%§:l~pointj the litera-

\—

ture does give some parameters for its use. This informa-
tion, however, is at best scant and may not be said to

apply to the geriatric user. The recent work at Gotesburg
on the affective meaning of color has shown that general-
izations linking hue to affective meaning is fruitless. The
dimensions of color meaning are far too complex to permit
oversimplification.

Finally, the use of color in the geriatric institution
was discussed. Although color may be a physical resource
for behavior setting identification, its current use is
based on insufficient knowledge~of geriatric needs and re-

Wm
sponses to color. To date, geriatric research has concen-

’__.——‘-.__.. .Aflfl .- -._

trated onpcolor detection.}bilities relative to the aging

“H

\.

 

visual system. Designers have hadwto interpolate these find-
ings to predict response to the informational character of
color. Such an interpolation should not be acceptable to
those using color as an orientational cue. Further research
at all levels of response to color communication is war-

ranted.

CHAPTER 4: HUMAN COLOR VISION

Introduction

 

In order to study, test, and generalize about color
perception in a specific population (21%;: the elderly),
the characteristics of 'normal' color vision must be under-
stood. It is also necessary to examine the techniques used
to characterize and measure the visual process and percep-
tion. This chapter will outline these subjects as they
relate to the general population. This then will provide the
basis for a comparative study of geriatric color perception.

Visual perception involves the interaction of radiant
energy from the physical world and the human brain. The
physiological system acts as receptor and detector of radiant
energy which originates in the external environment. Radiant
energy, or electro-magnetic energy, travels through space,
behaving like waves of varying frequencies (oscillations per
second), ranging from 1026 Hz (cosmic rays) to 102 Hz (elec-
trical disturbances). Of this broad frequency spectrum, only

14 and 8 x 1014 Hz are capa-

those frequencies between 4 x 10
ble of stimulating the human visual system, this band being
known as the visible light spectrum. Furthermore, wave-
lengths related to the visible light spectrum are perceived
as a range of hues from violet (380 nm) to red (700 nm).
Radiant energy is related to brightness. Color vision re-

search attempts to measure both the quantity and the quality

of the human response to light stimulation in terms of hue

52

53

and saturation brightness.

The Human Visual System

 

Light travels directly to the eye from a source or is
reflected from a surface. Upon entering the sensory system,
the energy is transduced, or transformed, by the visual re-
ceptors of the eye. This process is called isomerization,
the transformation of radiant energy to an electro-chemical
impulse, which is transmitted to the brain where it is trans-
lated and perceived. Thus, the human visual system may be
characterized as the receptor, transformer, and transmitter
of physical energy to the brain. A description of this
system may be focused at three levels: 1) the pre-receptor
level; 2) the receptor/transducer level; 3) the neural net-

work transmitter level.

The Pre-Receptor Level
The functions of the pre-receptor elements are to con-
trol, transmit, and focus light energy striking the surface

of the eye on the light sensitive visual receptors.

Cornea

The cornea is a transparent extension of the scler-
otic coat (112;: white of the eyeball). Its primary func-
tions are to initiate refraction of the light entering the
eye while protecting the interior of the eye from foreign

matter.

54

29211

The pupil is an aperture in the iris diaphragm through
which light enters the interior of the eyeball. The dia-
phragm action of the iris aids partially in adaptation to
the intensity of light impinging on the eye. In adaptation,
the muscles of the iris increase or decrease the size of
the pupillary opening (g;g;, 2 mm-8 mm). It is, therefore,
in part, a brightness control mechanism. Since radiant
energy admitted by the pupil is proportional to the aper-
ture area, a brightness control effect varies by a factor
of 16. Illumination levels, on the other hand, vary by sev-
eral orders of magnitude. Furthermore, pupillary size may
be related to visual acuity. As aperture size varies, it
controls the spread of lenticular illumination directly
affecting lenticular aberration. This effect will be dis-
cussed at a later point. Pupillary size is not totally
dependent upon brightness. Psycho-physical studies have
shown that pupil size is also related to subject interest,

arousal, and emotional state (Janisse, 1977).

Aqueous Humor

 

The aqueous humor is a water, salt, and protein fluid
between the cornea and the lens. It aids in light refrac-

tion and protects the lens tissue.

Lens
The crystalline lens is a transparent, pliable mass

taking a slightly convex shape in cross section parallel to

55

the optic axis. The primary functions of the lens are to
refract light and focus it on the retina. Through accomoda-
tion, ciliary muscles exert force on the lens causing the
pliable element to change its curvature. This allows the
visual system to focus over a wide range of distances of
varying illumination. Total lenticular accomodation is
about 60-70 diopters (£121: reciprocal of its focal length
in meters). The lens exhibits a fault common to all optical
instruments, viz. aberration. Aberration occurs when the
spread of illumination on the lens surface exceeds its
ability to bend the light to convergence at a single,

unique point on the retina. The image formed is blurred.

As stated, the size of the pupillary opening determines the
surface area of the lens which will be illuminated. As the
aperture widens to adapt to lower light levels, aberration
increases. In addition, chromatic aberration refers to the
inability of the lens to focus widely disparate wavelengths

with equal sharpness on the retina.

Vitreous Body

 

The anterior chamber of the eyeball between the lens
and retina is called the vitreous body. It is filled by the
vitreous humor, a jelly-like fluid, of chemical composition
similar to that of the aqueous humor. The approximately
spherical shape of the eyeball is maintained by a structural
framework of collagen fibers. Although the vitreous humor

is macroscopically transparent, it does contain floating

56

fibers of cellular material sloughed off from the retinal
membrane. This accounts for the threads or specks often

seen floating in the visual field.

The Receptor/Transducer Level
The functions of the receptor elements are to iso-
merize light energy focused on the photo-sensitive cells
and to gather the electro-chemical impulses in preparation

for transmission to the brain.

Retina

The retina, an extraordinarily complicated nervous
structure, is a thin membrane lining the back interior of
the eyeball. The retinal surface contains two distinct
regions, the optic disk and the foveal pit. The optic
disk, often referred to as the blind spot, is the point of
intersection between the optic nerve and the eyeball. The
£9233 is a shallow pit, placed slightly off-center on the
retina, where the sharpest image, or center of interest, is
focused by the lens. It is composed of tightly compacted

photo-sensitive cells and nerve endings. The macula lutea

 

is a pigmented region surrounding the fovga_in an elliptical
pattern on a horizontal axis covering a 5-100 region of the
visual field. This yellowish pigment decreases in density
as it approaches the center of the fogga. Although the
primary purpose of the macula is yet undetermined, it is
known to absorb some short wavelength light (Ruddock, 1964).

The retinal membrane is composed of layers consisting of the

57

photo-sensitive cells, the bipolar cells, and the ganglion
cells.
Photo-Sensitive Receptors:
Rod and Cone Cells

The rear layer of the retinal membrane is composed of
photo-sensitive cells called rods and cones as defined by
their shape. The human retina contains approximately 7 mil-
lion cone cells and 120 million rods arranged in an array
with cones centered behind the fgvga. Outside of the foveal
region, cones exponentially decrease in concentration, but
rods are increasing. The primary purpose of the photo-
sensitive cells is to isomerize the electro-magnetic energy
into electro-chemical impulses. In isomerization, light
striking a photo-sensitive cell is absorbed by cell photo-
pigment, bleaching the photopigment. This action triggers
an impulse to the brain. In a series of experiments on the
detection of light, Hecht, Schlaer, and Pirenne (1942) noted
the following conclusions: 1) sensitivity to light stimula-
tion increased with increasing time of dark adaptation;
2) the peripheral region of the retina was more sensitive to
weak stimulation than the fovea; and 3) that as light level
increased, the foveal region produced greater activity than
the periphery. The retinal location of the rods and cones
is directly correlated with these findings. It was con-
cluded that the ability of the rods to function at low levels
of illumination, called scotopic vision, was a function of

threshold (i.e., the point of light detection) based on the

58

bleaching properties of the photopigment. Cone sensitivity,
called photopic vision, is not activated until the level of
illumination is so elevated as to render the rods transpar-
ent.

Rod and cone sensitivity to monochromatic light also
varies as a function of wavelength. The human eye is not
equally sensitive to all wavelengths. In general, both
systems are more sensitive to mid-frequency spectral light
(i;e;, green and yellow) than to either of the extremes.
Furthermore, sensitivity varies between the scotopic and
photopic systems. The scotopic sensitivity curve peaks at
510 nm (green) while the photopic peaks at 550 nm (yellow).
This phenomenon is referred to as the Purkinje shift. Be-
cause of rod photopigment characteristics and the fact that
it bleaches at such a low level of illumination, the rods
are generally considered to be color blind. Therefore, the
primary source of color sensitivity and detection in the

human visual system exists in the cone cells.

The Bipolar Cells

The bipolar cells lie directly in front of the photo
sensitive receptors in the retinal membrane. They function
as "relay stations" of the electro-chemical impulses pro-
duced in the photoreceptors. Either several receptors ter-
minate at a single bipolar cell, or one receptor connects
to one or more bipolar cells. Therefore, there is some

impulse condensation at this level. The bipolar cells then

59

converge on the ganglion cells at the next level of the

retina.

Ganglion Cells

The ganglion cells, just below the retinal surface,
mark the point of major impulse condensation. The input of
a multitude of receptors is pooled at the ganglion level,
leading to the speculation that each ganglion cell is
responsible for 'coding' the stimulation of an area of the
retina (Kufler, 1953). Kufler's experiments established a
model of concentric ganglion receptor fields in which light
stimulates an 'on', 'off', or 'on/off' response. This re-
sponse is critical in brightness and hue perception as it
serves as an enhancement mechanism (g;g;, simultaneous con-
trast). Nerve fibers issuing from the ganglion cells travel
across the inside surface of the retina to form the optic

nerve .

Choroid Membrane

 

The retina is backed by the choroid membrane, a coat-
ing of brownish-black pigment. Its general purpose is to
absorb stray light, thus preventing a degraded image. It
has also been suggested that the choroid coating regenerates
the photopigments of the rod and cone cells (Padgem and
Saunders, 1975).

60

The Neural Network/Transmission Level

To date, the neurological foundation of sensation and
perception is still vague. Although experimentation has
mapped the general route of the electrochemical impulses
originating in the retina, it has yet to define the actual
cortical response to sensation. Historically, many psycho-
logists have believed that perception was a picture-in-the-
head version of the real world. Although some regions of
the brain respond when the retina is stimulated, it appears
evident that the neural response is considerably more complex
than this original hypothesis would suggest.

Nerve fibers issuing from the ganglion cells leave
the region of the eyeball by forming the optic nerve. Some
30% of these fibers (from the temporal side of the eye) move
directly to the Lateral Geniculate Nucleus (LGN). The re-
mainder cross the optic chiasma before proceeding to the
LGN. In the LGN an impulse synapse occurs. Fibers leaving
the LGN are routed to either the Superior Collitus for addi—
tional synapse or directly to the visual cortex at the base
of the brain. Studies similar to those of Kufler have led
to the mapping of receptor fields in both the LGN and the
visual cortex (Hubel and Weisel, 1961). These fields have
responded to hue, brightness, size, orientation, and direc-

tional movement of the stimulus.

61

Human Color Vision

 

Color vision begins with the ability of the human eye
to receive and detect light stimulation. Light entering
through the pupil is refracted, focused, and absorbed by the
visual system. An electro-chemical impulse then is trans-
mitted to the brain along the neural network. Although this
process describes the physiological mechanisms at work in
human vision, it fails to describe systematically the per—
ceptual experience of the physical environment. Historic-
ally, a variety of scientific disciplines have contributed
knowledge to generate a theoretical fraemwork concerning the
human experience of color.

In his experiments with light, Newton observed that he
could break down a beam of white light into the visible
spectrum using a prism. Furthermore, he demonstrated that the
spectrum could be combined again to produce white light.
This additive principle of colored light also could be ex-
panded to produce metameric matches to monochromatic lights.
These experiments led Newton to develop a circular model for
colored light mixtures. The color wheel, however, had its
flaws. It was found that although an admixture of red and
green lights did produce a yellow light, the mixture was
less saturated than either of the two original elements.

In 1802 Thomas Young proposed that a triangle, with
apices of red, green, and blue spectral lights, would be
more appropriate in that it corrected for the saturation

change. These lights were labelled the colored light

62

primaries. In 1924 Helmholtz adapted Young's theory to his
own theory of color vision and speculated that the eye must
contain three distinct fiber types with sensitivity to the
red, green, and blue primaries. He also proposed that this
type of configuration would lend itself readily to the de-
tection of all colors through the additive principle. This
theory is known as the Young-Helmholtz Trichromaticity Hypo-
thesis.

Microspectrophotometry has provided physiological sup-
port to the Trichromaticity Hypothesis. In his work with
cone cell photopigments, Rushton (1962) discovered two
distinct pigments called Chlorolabe (green-catching) and
Erthyrolabe (red-catching). He postulated, but did not
isolate, Cyanolabe (blue-catching). Each of these cone cell
pigments is capable of absorbing a broad range of spectral
wavelengths, but sensitivity peaks at either 570 nm (red),
535 nm (green), or 445 nm (blue). Figure 4 indicates the
absorption spectra of the three photOpigments. Therefore,
the photopigments in the cone cells possess the potential
to detect all discriminable hues in the visible spectrum
through the additive principle.

The Trichromaticity Hypothesis, however, does not
provide the entire explanation for color perception. It
contains two main flaws: 1) it concerns itself only with
chromatic color perception, making no allowance for achro-
matic colors, and 2) it ignores the complementary process

which precludes the existence of greenish-reds and

Proportion of Quanta Incident on
Cornea Absorbed By Photopigment

.20

.18

.16-

.14

.12'

.10-

.08

.06

.04

.02

.00

63

 

F—
/ L 1

400 440 480 520 566 —'6oo" 640 .680
Wavelength (nm)

Figure 4: Absorption Spectra of Three
Photopigments of the Human Eye

64

yellowish-blues. In 1870 Herring addressed these problems
when he proposed the Opponent Mechanism Theory. Herring
contended that the visual system operated a switching mech-
anism of complementary colors (g;g;, 'on' yellow/'off' blue).
He hypothesized three sets of opponent mechanisms: yellow/
blue and green/red, corresponding to the psychological pri-
maries, and black/white controlling for value changes. The
work of Hurvich and Jameson (1957) has provided some exper-
imental support to the Herring theory. Their opponent
mechanism model places the process at the neuron and ganglion
cell levels rather than in the photoreceptors. Moreover,
instead of an 'on/off' mechanism, Hurvich gt al_have pro-
posed an excitatory/inhibitory effect on the opponent mech-
anism centers. For example, a yellow stimulus would excite
neural activity signaling yellow while concurrently inhibit-
ing blue output.

The Opponent Mechanism Theory also considers black
and white detection. Often referred to as the luminosity
unit, this system accounts for the lightness and darkness
of all four primaries. It is excited/inhibited equally by
either red, green, yellow, or blue centers, or in combina-
tion to produce gray. This allows not only for perceived
value differences, but also for the rather neutral chroma-
ticity of low luminance surfaces (above cone threshold).
Finally, the studies of Wagner, MacNichol, and Walborst
(1960) at the ganglion cell level seem to reinforce further

the Opponent Mechanism Theory. They have mapped a

65

color-coded ganglion cell to find areas of 'on/off' re—
sponse that can both be excited and inhibited by red and
green lights. Research beyond the ganglion cell level is as
yet inconclusive.

Recent studies have supported both the Young-Helmholtz
Trichromaticity Theory and the Herring Opponent Mechanism
Theory. These two positions, once thought to be in direct
opposition, now are perceived as being complementary. The
Trichromaticity Theory relates to color sensation at the
receptor level, whereas the Opponent Mechanism Theory re-
flects post-receptor activity. Together they yield an ade-
quate model of the process of color vision. And together
they have been employed by ophthalmologists in the prepara-

tion of color vision tests.

Color Vision Testing

 

Thus far, this chapter has considered a description of
the human visual system and the physiological evidence sup-
porting a theoretical framework of color perception. Al-
though a detailed study of the ocular media and the neural
pathway is necessary to understand human color vision, it
does not provide an analysis of perception. Color vision is
a complex interrelationship of a human organism and its
environment. Color vision testing has been developed in an
effort to expand upon physiological data by characterizing
the experimental component of perception. Its primary ob-

jective is the detection of the individual's ability to

66

discriminate colors along the hue, saturation, and value
axes as they relate to the population mean. It is concerned
with assessing man's physiological abilities in contrast
with psychological tests, which include the intervening vari-
ables of psychological, sociological, and cultural sets.
Color vision testing may be categorized into two primary
areas: 1) laboratory assessment of the color vision system,
and 2) clinical assessment of the functional ability of the
system. Their objectives are to test discrimination ability
(i;g;, the observable difference between given energy rela-
tionships) and color confusion (i;g;, the false perception

that one mistakes one hue for another).

Laboratory Assessment

Colorimetry, measuring color vision efficiency, is ac-
complished under rigidly controlled laboratory conditions.
Its objective is to characterize discrimination ability in
detecting monochromatic wavelengths and their luminosity
function. Measurement is based on detection of a threshold
difference called the just noticeable difference (j.n.d.).
Threshold denoted that point where the subject accurately
reports a difference 60% of the time. The concept of the
j.n.d. is derived from the combined work of Weber and Fechner
in the mid-1800's. In studying luminance difference thres-
holds, Weber noted that the threshold increment for any
stimulus relative to its surround is a constant (C = —g).

Fechner expanded on this by deducing that luminosity

67

increased as a logarithmic function of luminance in equal
j.n.d. steps. Colorimetry employs these concepts to test
brightness discrimination ability. Similarly, j.n.d. steps
are calculated for hue differences. The Nickerson-Stoltz
Formula (1942) was devised to measure color difference ( c)
by employing the American National Bureau of Standards color
scales. In this measure, 1 NBS unit is equivalent to 5
j.n.d.'s as perceived by the normal observer under ideal
viewing conditions. The measure of hue and luminosity dis-
crimination ability is performed with the subject under
rigid experimental control, usually positioned in an appara-
tus which limits his freedom of movement, pupillary size
opening, and level of adaptation to background luminosity.
The subject is initially presented two matched fields of
monochromatic light. The experimenter then varies one field
until the subject reports that the two fields no longer
match. Discrimination ability is determined by the number
of j.n.d. steps required to detect the difference. Although
the colorimetric study of color vision yields data of high
reliability, it has severe drawbacks as an instrument for
popular usage. It requires a battery of optically sophisti-
cated instruments, a rigidly controlled environment, and a
trained subject willing to spend considerable time and

energy in performing the test.

68

Clinical Assessment

Clinical tests assessing color vision have been devised
to provide a more readily manipulated instrument for large
sample testing. Their primary objective is to detect color
vision defects in the population by measuring discrimination
ability and the loci of color confusion characteristic of
deuteranopia and tritanopia. Lakowski (1969) conducted a
comprehensive survey of clinical color vision tests cur-
rently used in the field, condensing them into four primary
categories: 1) anomaloscope discrimination tests; 2)
Farnsworth-Munsell 100 Hue tests; 3) pseudo-isochromatic
tests of color confusion; and 4) color aptitude and memory
tests. The basic elements of test comparison were mode of
appearance, complexity of task and stimulus, and administra-
tive considerations. Specifically these elements are:

Mode of Appearance: According to Katz (1935), color
is perceived in a spatial/temporal context determining its
mode of appearance. Color vision tests are presented in two
modes: surface mode, where color is perceived as belonging
to a plane (218;: paper), and film mode where color is per-
ceived as occupying a void (218;: peephole effect).

Complexity of Task and Stimulus: The complexity of the
task will affect the subject's performance, and, thus, may
be an intervening variable clouding test results. For
example, the test may require the subject to read numerals,
detect figures, or arrange color chips. This assumes either

a prior knowledge of the symbolic context of the stimulus or

 

69

a cognitive process sufficiently developed to understand a
scaling process. Stimulus complexity involves the varia-
tion of hue, saturation, and brightness in the test. Band
width and brightness range of individual stimuli may vary
along the visible spectrum within and between tests.

Administrative Considerations: Administration of the
test involves not only the instrument, but also the emo-
tional state and attitude of the subject, the expertise of
the experimenter, and the environmental factors influencing
test results. These include illumination level, thermal and
acoustic conditions, viewing angle, and retinal angle of
subtense of the stimulus. As both foveal and parafoveal
stimulation are related to the perceptual experience, stim-
ulus location in the field is a critical factor.

Considering these elements as factors in the design
of color vision tests, the four types of tests as outlined
by Lakowski are:

Color Discrimination --
Anomaloscopes

 

 

The anomaloscope has been developed to provide a
clinical test of color vision yielding a greater control of
data than other clinical tests. They are devised to detect
discrimination ability based on the process of metameric
matching. ‘Metamers are defined as a pair of hues which
differ in spectral composition but are perceived as being
colorimetrically equal. Employing both the Trichromaticity

and Opponent Mechanisms Theories, the test requires the

70

subject to match a monochromatic light with an admixture of
two light primaries. Brightness fluctuations, inherent in
hue changes, are controlled by the instrument. Using the
film mode of appearance, the instrument places both the
standard and the test stimuli in the field of vision. Ret-
inal angle of subtense ranges from 1030' to 3015'. Discrim-
ination ability is determined through repeated matching
exercises from which the matching range (MR) and the mid-
‘matching point (MMP, mean of the MR) may be calculated. The
scores then may be plotted graphically and compared in per-
centile rank with population statistics developed for that
particular instrument. While the anomaloscope yields a
precise calculation of hue discrimination ability, it re-
quires rigid control of the environment as well as the sub-
ject, considerable training and practice, and a high degree
of concentration for extended periods of time. As a result,
a study employing the use of an anomaloscope usually relies
on data collected from a small sample in order to generalize
to a population.

Color Discrimination/Confusion --
Farnsworth-MunSEII 100 Hue Test

 

 

The Farnsworth-Munsell 100 Hue Test was designed to de-
lineate color confusion lines, and also to quantify minute
differences in color discrimination ability. The instrument
is prepared in the surface mode using the Munsell Color
System. In testing, the subject scales a series of color

chips, according to hue difference, between two given

71

standards. The chips are calibrated for equal saturation
and brightness within the Munsell system. Retinal angle of
subtense of the individual color chip is 3015', and the mean
j.n.d. steps is 2.2 NBS units. Test results are determined
by the number of errors caused by transposition of chips

and compared in percentile rank with a population median
established by Farnsworth's 1957 study of industrial work-
ers. Because the lOO-hue test is capable of measuring dis-
crimination ability, it may be an appropriate tool for
studying visual system deterioration if performed under con-
trolled experimental conditions with subjects possessing

the cognitive ability to understand a hue gradation series.
It does have, however, its drawbacks, as will be discussed
in Chapter 5.

Pseudo-Isochromatic
Tests (PIC)

 

 

The general objective of the popular PIC tests is to
classify defective color vision according to color confusion
types. They are based on the Herring Opponent Mechanism
Theory and are developed in relation to opponent pairs.

The instrument is a series of color plates in the surface
mode composed of colored dots ranging from 2° to 10° angle
of retinal subtense. The colors contain both broad and
narrow spectral bands, varying reflectances, and a wide
variety of j.n.d. steps (18-50 NBS units). The dots are
designed to vary along known color confusion lines (g;g;,

red/green), with one set forming the figure and the other

72

forming the background. The subject's task is to detect
and identify the figure which may be arabic numerals or
geometric shapes. Data obtained from PIC testing yield
primarily quantitative measures of color confusion, and
secondly, general qualitative results. For example, some
transformation type plates, in which the defective subject
detects a figure different from the norm, are capable of
measuring a degree of color discrimination ability by study-
ing perceived pattern clarity.

There are two primary concerns with the use of PIC
color plate tests. First of all, test results provide only
a probability measure of color defect, because the degree of
color confusion lies in the criterion established by the ex-
perimenter (245;, error score related to degree of confu-
sion). Secondly, the PIC are not structured to distinguish
accurately between their measurement of color discrimination
and color confusion. Therefore, these tests are suspect in
their ability to assess color vision deterioration caused

by chronic disease or aging.

Color Aptitude and Memory Tests

 

A variety of clinical tests have been developed in the
last forty years to measure color aptitude and memory rather
than discrimination ability or color confusion. They are
particularly meaningful in industrial applications where a
worker must be able to discriminate and sort colored mater-

ials, but their usage is becoming more popular for the study

73

of general populations. The Color Aptitude Test designed
for the Inter-Society Color Council (C.A.T.-I.S.C.C.) by
Dimmick in 1942 is meant to assess the subject's ability to
discriminate saturation differences. The test field is a
fixed standard of four rows of colored chips each subtending
an angle of 4030' on the retina. Each row contains a random
distribution of saturations, with j.n.d. steps ranging from
0.8 to 3.0 NBS units. The subject matches a set of test
chips to the standards, and scores are compared in percen-
tile rank to the sample population.

Color memory tests study the subject's ability to
remember hues. Employing a simplified lOO-Hue Test, the
subject is presented a standard for five seconds. This is
followed by a rest period of no stimulus. The subject then
selects a test stimulus that matches the original standard.
Scores are calculated by percentile rank.

Table 1 summarizes this discussion by comparing the

characteristics of the four major categories.

Conclusion

 

This chapter has outlined the mechanisms involved in
visual perception and discussed the techniques used to test
human color perception. This was necessary in order to
develop a model and the types of criteria currently used to
judge that model. There has been little effort to evaluate
these criteria, particularly as they relate to the testing
of the elderly. The following chapter examines color vision

in a geriatric population. Throughout that chapter, we will

74

study the application of color vision research to a specific
population and the conclusions currently accepted in the
field. All of the tests described in this chapter have been
employed to test the color vision of elderly samples with

varying degrees of success.

 

ouuuovo:
ouuuuvoz

vuoomucouu
adage mo nonssz

.OfiOQ
c.n u m.o

manna omcuuu<

30A
ouuuovo:

huuouuuoo vuou
nououn mo uoaaaz

00H 1 ON
cm n ma

shaman uuouon

ems:
cams:

coconucuuu
adage mo Hoaasz

.nHOfi
n.n : 9.0

nuance omacuu<

and:
sang:

uaqon magnuuqauvqa
\omnnu wcasouu:

.ndon u .cnoH

Hana uwuoamuua
:« omenso 0:: ouoz

coauoouon
couuacaaauoaua on:
6% huqsuaaaaux

Houucou mo ooumon

wcuuoom

eucauuaam
o~mc< Hacauom

Angus: maze .a.z.n

same

 

commuam oouwuam ooamuam Baum oucuuuunnc mo ova:
moduua vasoumxouawdu
couuuusuao wsuauom uuov _ aoquoa
:« amuse on: wouosoo uo uouumm uoaoo :« amaze as: mausouua aquoaauoz unshom
auuumm wand . semiannuoz ucocomao .
uoaoo Havana: uaunooz unocoaao auunhn uoHoo Havana: and huuuauuaousuauh «anon Anuuuouounh
couuucwsquu nonzu couasmcoo
noun couuuusumm uoHoo uoouon couuucaauuuodv on: couuwcuaauoawv on: uo>uuooeno
uuous ouuusouSanH uous o:=:co~
ovauuud< nodoo :ovaoom aauucaanuuosmcuum nonouuo~aaoa< aowuuauuuoauuno

 

 

scuuaawaauooan on: no acuuoouoa ca cohofiaau

mummy acoucaau

"a cans?

CHAPTER 5:
COLOR VISION CHARACTERISTICS OF A GERIATRIC POPULATION

Optimal performance in a man/environment communication
system that employs color cues for information transfer de-
pends upon the user's ability to receive, detect, and code
stimuli. Presumably, all individuals possessing the char-
acteristics of 'normal' color vision/could participate

WN-
equally in the reception/detection process and, thereafter,

 

differentially respond according to individual knowledge and
acceptance of established code. Impaired color vision could
diminish ability to participate in such a communication
system. Thus, the designer employing color as an orienta-
tional cue should be aware of possible deviations from the
norm among the user population. In the last fifty years, the
field of ocular gerontology has concentrated on the charac-
teristics of the aged visual system relative to the norm.
Systematic study has revealed that certain ontogenetic
changes occur in the human visual apparatus which render the
aged eye histologically and chemically different from the
normal system discussed in Chapter 4. This chapter will
outline these changes relative to the aging process and dis-
cuss the resulting implications for the detection of color
cues in the environment.

Ocular gerontology studies the visual system with age
as the independent variable. Research generally follows

one of two specific modes of investigation with transverse

76

77

or longitudinal techniques. Transverse, or cross-sectional,
studies attempt to identify age differences between sample
cohorts, the population being divided by decade from child-
hood to old age. This type of study provides a good indi-
cator of structural changes in the visual apparatus. Longi-
tudinal studies, on the other hand, are develOped to measure
ontogenetic changes in the same subjects through time. It
provides a reliable indication of functional changes in a
given system. There are, however, serious drawbacks to the
longitudinal study. First, there is considerable attrition
because of subject withdrawal from the parent population.
Intervening variables, such as disease or accident, may
affect vision more radically than aging. Finally, advances
in measurement techniques may invalidate correlations of
prior work. Therefore, the bulk of current research on both
structure and function is of the transverse type. This does
raise the problem of validity in transverse studies of
functional changes due to aging. Beyond the problem of
developing sample cohorts of comparable size and composition,
it remains questionable whether one measures actual onto-
genetic changes or merely generational differences. This is
particularly true of color vision studies. The perception
of color is tied uniquely to cultural patterns and personal
experience. As these experiences may differ among genera-
tions, they may play a significant role in determining age-
related differences. To date, this problem has yet to be

addressed by psycho-physical color vision research dealing

78

with the elderly.

The Aged Visual System

 

Although methodological difficulties must be consid-
ered in any discussion of ontogenetic functional changes in
vision, both longitudinal and transverse research supply a
relatively complete analysis of structural changes. Paral-
leling the description of the normal visual system outlined
in Chapter 4, it may readily be discerned that the aged
physiological network is degenerate and should result in
diminished sensitivity to visual stimuli. In his classic
work, Thegéging’Eye,,HEale (1963) provides a systematic
study of the morphological changes in the visual network,
accompanied by supportive evidence as to functional changes.

Briefly summarized, they are as follows:

The Pre-Receptor Level
In the normal system, the pre-receptor elements con-
trol, transmit, and focus light on the retina. With age,
developmental changes in their structure lead to a decline
\ _—
/6£sin the total amount of light entering the eye, the spectral
distribution of that light, and the quality of the focussed

image.

9 M
Cornea fl Mr
While the cornea undergoes considerable ontogenetic
change, this generally affects the appearance of the eye

more so than its functional attributes. There is little

79

appreciable change in corneal diameter and thickness
(Berliner, 1949), but there is a slight flattening of the
curvature (Hogan and Zimmerman, 1962). Fischer (1948) re:

. \
ported an increase in the density of the cornea stroma an;
“"

described a concomitant increase in light scatter. Maurice
__.___.__...._.—-—---"‘*"'"' "‘W
(1957) noted the scatter was greater for short-wave than

  
  

 

 

long-wave light, suggesting small-particle (Rayleigh) scat-
tering, and accounting for the small, but significant in-

crease in corneal light loss (Boettner and Wolter, 1962) and

 

the radual yellowing of the eye with age. The epithelium
W
//”/”becomes slightly dehydrated resulting in a slight increase

in the refractive index and a decline in eye luster (Fischer,
1948). The chemical composition of the cornea also changes

with age resulting in the formation of the arcus senilis, a

 

lipid deposition that blurs the definable circle between

the cornea and sclera, and the Hudson-Stahli line, a pig-
mented line in the lower region of the cornea. One conse-
quence of such changes is a possible reduction in peripheral
vision because of blurring (Colavita, 1978). These chemical
changes are accompanied by the accumulation of pteridine, a
fluorescing substance sensitive to a stimulus of

(Cremer and Bartels, 1962).

Pupil
A gradual decrease in pupillary diameter with age has
M

been documented in both dark- and light-adapted eyes

(Birren, Casperson, and Botwinick, 1950 and Leinhos, 1959).

80

Weale (1963) suggests that this decrease may be accounted for

by a gradual decline in the depth of the anterior chamber_

 

 

 

 

I

 

 

caused by lens thickening or slight advancement of the lens.
This is complicated further by an increasing dominance of
parasympathetic tone in the sphincter muscles (Kumnick,

1956) and thinning and rigidifying of the iris. The fact
remains, however, that accompanying senile miosi§_(i;e;,
contraction of the pupil) is a diminished pupil area because
it is proportional to the square of the diameter, and, thus,

43%.retinal illumination is reduced. Weale calculated that onlng

W—
<§EEEEEEEBLEEE-EESEEE_Ef light reaching a 20-year retina would)

fall on that of a 60-year-old. Robertson and Yutkin (1944)

E

‘1

had earlier confirmed this experimentally by noting an age-

 

 

 

 

 

‘

related elevation in absolute threshold to white light that
was inversely proportional to pupil area. Threshold sensi-
tivity also can account for the apparent increase in time
for dark adaptation noted by McFarland, Domey, Warren, and

r)", _7 (-
Ward in 1960 (Weale, 1963) . Dipigmentation of the.[w""]‘é‘*é

also a senile process, results in pigment fragments floating
W‘— #-‘

 

in the anterior chamber. These fragments may adhere to the

cornea or lens, leading to some, albeit slight, deteriora-

 

tion in visual acuity.

w
7") “ @ Boy
J

‘_‘

While there appear to be no recorded chemical or bio-
chemical changes in the aqueous humor, Becker (1958), noted

an increase in outflow resistance. While this could result
W. M- MW

81

in an increase in interocular pressure, there is no signi-
ficant pressure variation between ages 15 and 75 (Aurrichio
and Dectallevi, 1959). Therefore, there seems tg_bg,little_____

evidence that an change occurs in the aqueous humor affect-

ing vision in the later years.

Le_n_§_

Because of its important role in visual accomodation
and acuity, and its ability to perform metabolic activity
while isolated from the blood supply, theficrystalline lens

M

has been the subject of much research. Geriatric lenticular" 1,
research is prompted by the high incidence of cqg§¥§‘t”ih. E5/j{;
aging populations; 65% between ages 51 and 60 rising to 96%
after age 60 (Alvaro, 1953). It is also prompted by the
decline in light transmission by the lens (Said and Weale,

1959).

{Elaborationjon physical changes in the lens requires a

T.

brief summary of its structure and development. The lens is
formed ofzgctodezméijcells which are pinched off from the
optic vesicle during fetal development. This then-hollow
structure consists of anterior and posterior cells. In

\qpii~\_,. \,,_\\___ __i
development, the posterior cells elongate into the primary
lens fibers, hexagonal in shape and with a length some 1,000
times their original diameter (Figure 5). Throughout life
the lens continues to grow by mitotic divisions of the

anterior cells at the lens equator, forming the secondary

lens fibers. This results in a gradual increase in

82

o .
@090 A32???”

03>
Equato Q09

Cells )

Posterior
III" Lens Fiber
21>

Figure 5: Horizontal Section of a Developing Lens V

 

 

 

 

equatorial diameter first noted by Smith (1883) and construed
in the literature as lens thickening. Weale argues that
attempts to verify this conclusion experimentally are sub-

ject to doubt because of methodological limitations. ~§§X§£l——«

(f’theless, with age the n er of mitotic divisions declines

and lens fiber nuclei apparently dissolve (Ham, 1969). Thus,

 

 

 

‘ \\
/i:gszl onti rowth, or lamination, and compression of lens

fibers, accompanied by nuclei dissolution cause the older

[—
___ more an amorphous mass than its younger coun-

 

     
 

 

lens to

' -‘ Limw—ua -na-I.-- ------m—-—

 

terpart-

 

Lenticular mass increases some three times its neonatal
value of 80 mg (Salmony, 1961). Volume, however, tends to
increase at a slower rate because of fibrous compression,
thus, gravimetric density increases. It is often said that

\holder lenses are harder than younger ones. Weale (1963)
contends that anexp;rimgntally‘viablefmeasure of hardness

has yet to be developed. It has been shown, however, that

older suspensory ligaments, affecting elasticity of the

83

lens, break with a stretching pressure of 2 g weight at 1-2
mm while a younger one requires 30 g weight (Barraquer,
1924). Thus, presumed hardness may be merely an artifact
of brittle ligaments.

Three other structural changes in the aging lens have
been noted, but their significance is not yet fully under-
stood. Goldman (1937) found that histological examination
of the equatorial cross-section showed disjunctive accessory
stripes similar to growth rings on a tree. These disjunc—
tions appeared at approximately four-year intervals. Weale
(1963) feels that these may relate to lenticular light
scatter, affecting color vision. Secondly, Duverger and
Velter (1930) noted the appearance of a circular region of
shagreen (£iEi» rough granulations) on the central one-third
of the anterior nuclear surface. And finally, Vogt and
Lussi (1919) found fork-shaped ridges in the same region.

As stated, the optical importance of these findings requires
further clarification.
\\Further reference to lenticular growth provide§_§’

suitable bridge to a discussion of chemical changes attri-

W
butable_to\aging;__ns mentioned, embryonic development of
<//,__

posterior cells form the primary lens fibers, whereas

 

mitotic divisions of the anterior cells form the secondary
fibers. These two types of fibers are differentiated as
forming the nucleus and cortex of the lens. Varying chemical
changes in these two parts may affect visual acuity and

light transmission in serious ways. Significant chemical

84

changes include a shift in fluorogen accumulation, apparent
dehydration, and an increase in insoluble protein level.
Although it is difficult to determine true fluorescing from
extinction due to absorption and scatter, Klang (1948) was
able to detect a rise in the fluorescence ratio of violet

to green light with concomitant increase in the red to green
ratio with age. He also isolated two fluorescing substances,
lactoflavin and dimethyl alloxazimes. In comparing fluores-
cence in the nucleus and cortex, Jacobs and Krohn (1976)
found a definable red shift in the nucleus at 375 nm but not
in the cortex. Furthermore, this shift was not found in
either at 400 nm. These results indicate that there is not
only a change in predominant wavelength fluorescing intens-
ity, but also that fluorogen accumulation varies between

the nucleus and cortex.

is said to be characteristic of most

‘légi駑EEEEEE§$V This also has been said of the lens (Bellows,
1944). «13‘32Eualityi experimental data fail to confirm

this conclusively (Weale, 1963). It appears that a finer
~distinction—must‘be'made. Lowry and Hastings (1957) con-
tend that intracellular water remains relatively constant
while extracellular content may actually increase. This
could result from a shift in the Na/K ratio with increasing
extracellular sodium concentrations (Weale, 1963). This
ratio is again found to increase as one moves from the
cortex to the nucleus (Lebensohn, 1936). The question re-

mains open, but important, since this could have a bearing

85

in clarifying why the refractive indices of the lens remain
relatively constant as visual acuity diminishes.
The increase in insoluble protein level in the lens is

important optically because the.’ and refractive

EEEE§>of the particle affect scattering of the light. Lens

 

scatter has been shown to increase linearly with age beyond
age 40 (Wolf and Gardiner, 1965). Furthermore, one of the
primary factors in lenticular transparency is the high con-
centration of_§gluble_prgtein;‘ The data of Krause (1934)
on bovine lenses showed a definite increase in the insoluble/
soluble protein level with age. This has been attributed to
a transformation of the soluble protein alpha-crystalline
into an insoluble protein (Mok and Waley, 1968). The new
protein, or its state, have yet to be identified. Spector,
Freund, and Augusteyn (1971) have, however, noted that in the
transformation process alpha-crystalline increases in size,
and that this increase occurs only in the nucleus of the
lens. Further study into the new insoluble protein obvious-
ly is warranted.

Given this broad physiological summary of the lens, it

would do well to point out the major effects on color vision,

namely<absorptiofl and light/ggééggi. Said and Weale (1959)
performed a major study of age;;gl§£edi£h§E§E§_iP iE_Vivo ‘

lenticular absorption. Their data indicate that optical

 

 

density at different wavelengths varies for all ages (i.e.,
4-63) but clearly rises with age. The rise, however, is not

uniform for all wavelengths. Optical density increases

86

continuously, but at a faster rate as one approaches the
short-wave end of the spectrum.to about 430 nm. Thereafter,
the increase is less steep. Their data was found to be con-
sistent with Hess (1911) measuring absorption through sensi-
tivity threshold in a group of unilaterally aphakic observers
and Boettner and Wolter (1963) measuring transmission spectra
of extirpirated lenses (Ruddock, 1972). Their conclusions
indicated that absorption by pigmentation of the lens was a
major factor. This unidentified pigmentation is often re-
ferred to as lenticular yellowing. Wald (1949) and Burch
(1959) pointed out, however, that absorption varies too
radically within age groups to be the only major factor.
Furthermore, Cooper and Robson (1969) were not able to ex-
tract more pigment from.older lenses than younger ones.

It appears that light scatter plays a greater role.
Goldmann (1964) and Ruddock (1965) found that scatter, fol-
lowing Rayleigh's Law, can account for much of the shift in
optical density as well as lenticular yellowing. One will
recall that the increase of insoluble proteins and possible

discontinuities of lenticular laminations play a major role”
\\/~_i.—i 94’-%—— ~__l

 

in light scatter.

Vitreous Body

 

Senile changes in the vitreous body usually do not
affect the visual process unless they become pathological
in nature. The primary degenerative occurrence is a slight
breakdown or shrinkage of the fibrular structure; its cause

is unknown. In the 70's and 80's there may be an increase

87

of floating material in the vitreous humor, but this appears
to cause little more than visual distraction. It may lead

to some increase in light scatter (Weale, 1963).

The Receptor/Transducer Level
The primary functions of the retinal layers are to
isomerize light energy and to gather electro-chemical im-
pulses for transmission to the brain. To date, it is gener-
ally accepted in the literature that there is little senile

degeneration in these elements and their functional ability.

Retina

The retina appears to be relatively resistant to senile
change except for a slight thickening which renders blood
vessels less visible (Weale, 1963). There is also a gradual
thickening of the walls of the retinal arteries (Belleto,
1953), and some deposition of collagen fibers on capillaries
of the optic nerve (Hogan and Zimmerman, 1963). Perhaps
the most significant change is the yellowing of the macula
lutea, since this could result in greater absorption of
short wavelength light. Although there probably is some
absorption, Ruddock (1965a) demonstrated that this would not
be a major contributing factor in color vision. Rod and
cone cells remain intact and regeneration of the photopig-

ments remains constant (Weale, 1963).

88

Choroid
While the choroid membrane shows some thickening and
loss of elasticity, it is of little intrinsic interest in

color vision studies.

The Neural Network/Transmission Level

Geriatric research of degenerative changes in the
brain is still in its infancy. Thus, any attempt to iden-
tify changes relative to the visual process are futile at
this time. Recent psycho-physical research in visual
sensory/perceptual skills should help to fill this void.

It has been the purpose of this account of the elderly
visual system to identify physiological elements that may
impair color vision. It has dealt with the aged eye as an
apparatus potentially able to detect stimuli. In summary,
it may be seen that the pre-receptor elements exhibit suffi-
cient degenerative change to affect ability in color detec-
tion. Obviously, further work is required to complete the
picture, particularly regarding the neural network. For it

is in the brain that perception of the stimulus occurs.

Results of Color Vision Testing

 

To move from analysis of potential sensitivity to a
discussion of organized perception is a large step, as has
been discussed earlier. It requires a concomita t under-

? Mi) 9 50:
standing that perception involves the nteraction f detec-
tion andxestablishe cogs. Furthermore, it implies that

"J...” buoy—r
this process is measurable if given certain standards. The

89

purpose of this section is to describe and discuss the per-
ception of color among elderly subjects based on available
data, but ever mindful that a dramatic number of assumptions__

have been made, There is sufficient motivation to do so;

 

V:

however, if the designer is to be given the information and
tools for developing appropriate environments.

A review of Said and Weale's 1959 study of spectral
sensitivity serves as an adequate bridge. In this study,
it was found that sensitivity to monochromatic wavelengths
declined with age and that the decline was greater for short
wavelength stimuli. Using a Wright Trichromatic Colorimeter,

Ruddock (1965a) surveyed color vision changes with age

fl

EEng_éflfl_ohserxer§‘_ He attempted to determine not only

sensitivity, but also to distinguish pre-receptor and re-

W ._._—_

 

 

 

 

ceptor roles in causing any changes. The first part of the
W V 4
study measured. sensitivity to wavelengths at 590,

 

 

 

530, and 490 nm as this could disregard the effects of the

pre-receptors. It was found that there was only a sli ht

 

 

decline in wavelength discrimination ability for short wave-
WA A‘—

 

 

 

length§;,lA forced-choice test showed no difference. s‘fi
Ruddock contended that the data suggested, "that the small
positive correlation between j.n.d. discrimination step and
age is an artifact, due to technique" (Ruddock, 1965a, p.
41). This initial test was followed by an examination of
matching ability to a[§TITBTlstandard light source using the

__-______,,_
same apparatus (Ruddock, 1965b). This time a significant

 

difference was found among age groups2with the elderly having

-.. w-v—‘fi

90

a diminished short wavelength sensitivity. Thus, their

C'— ‘

matchin coo inates were shifted toward red and green. He

then applied this experimental data to a mathematical model

 

 

for predicting the response of a 65-year-old observer to the

unsell 100 Hue est. The results will be discussed later.

Clinical Assessment

 

Applying the various clinical techniques described in
Chapter 4, several experiments have been conducted to charac-

I)
terize elderly color discrimination ability and<loglfoffifi ~

A
v

 

‘-

color confusion. These will be described according to the

 

technique employed, with a note of caution that the poten-

tials and limitations of each technique be borne in mind.

Color Discrimination --
Anomalbscope

 

 

The primary problem in using an anomaloscope for
\

_‘d

testing color matching ability among age groups lie§_in_‘-

errors of refraction, both in and of themselves and also as

4

v

a side-effect of chromatic abberation; Millidot (1976)

\ A

‘7

demonstrated that chromatic abberation diminishes with age

 

 

because of thej increase of presbygpia , Wienke (1960) has
shown that myopia requires less, and hypermyopia‘more, red
in a red/green match of yellow than does normal ViSiQE11»

’ 7 fl

Both of these problems may be corrected by the use\gf\a_ygry;'

 

small exit pupil. Thus, only studies applying this method
r\———-._/————~———I
will be considered.

Boles and Carenini (1954) performed the first accurate

91

7(1le W

anomaloscope testing comparing age groups from 20 to 80.
Degeneration of discrimination ability in color matching
was found to begin in the third_dggade, but§rgm§ined‘con:i
3M1 thereafter, it W
Stiles and Burch (1959) found a small, but significant cor-
relation of continuous decline in matching ability with age
and also noted considerable variation within age groups.
They concluded that the correlation varied with the amount
of pre-receptor absorption in the lens and macular pigment
as much as actual aging. Lakowski (1958) employed the
anomaloscope to test color confusion in a non-selected

sample of 500. It was found that the number of errors on the

Efglgreen_te§£‘increased after/age 60) but the sample was

\r’
not significant. In both the yellow/blue and violet/blue-

 

 

 

green tests he found a highly significant decline in dis-
crimination ability after age 40. There was an increase in
anomalous readings as well as total misreadings. Thus
experimental use of the anomaloscope in testing age differ-
ences in color discrimination ability has shown a red shift
with age. This shift, however, is not clearly defined as

v

to the amount of blue sensitivity that is lost.

 

Farnsworth Munsell 100 Hue Test

 

The earliest Munsell 100 Hue Test applied to elderly
subjects was performed by Smith (1943). Employing 199

subjects (age 5-87) he found a definite drop in ability to

 

 

match color chips in all three dimensions of e value and
..‘_’,_,1 _117

 

 

92

chroma after age 65. Chroma, however, was least affected.
His results also showed that ability to discriminate yellows
actually increases in the post—65 group. The general order
of decline in the remaining hues was green, purple, blue, and
red. These results are interesting in view of other studies.
He attributed the results to intervening variables noting,
"it is suggested that age differences in color matching
ability are predominately determined by attitudinal and
learning factors rather than by receptor physiology" (Smith,
1943, p. 223). Regarding the test, he noted that certain
inequalities exist in the Munsell system and that illumina-
tion levels above 10 f.c. did not enhance ability. Ruddock
,————___,
]T__-(l972) applied a mathematical model of spectral sensitivity

to determine response on the 100 Hue Test. His model indi-

 

 

 

 

cates that, "...the older observer should be less able to
discriminate between (certain) ; es of hues (s ecificall
)6 e- P >',_

 

 

 

 

 

the blue-green hue samples numbered 45—55 and red hue sam-
[ ples numbered 80-85 and 1-5):‘(Ruddock, 1972, p. 464).
Moreover, he states that the model is confirmed by experi-
mental data of Verriest, Valdevyvere, and VanderDonck
(1962) and Burch (1964), and concludes that pre-receptor

transmission factors affect discrimination ability. It
m

"appears that there is a definite conflict in interpretation
Am

A _—
v

of results: Ruddock stating that this is an indication of

 

subject sensitivity and Smith suggesting that it may be an
artifact of the testing instrument. This controversy has

yet to be resolved. Ruddock also discusses the effect of

93

illumination on test results by noting that adaptation to the

light source could influence matching ability.

Pseudo-Isochromatic Tests

In 1942, Tiffin and Kuhn attempted to test age-related

M
color vision using 7000 industrial workers and a non-

 

 

.—

descript P.I.C. test. “All 7000 were tested for red/green
K J

 

confusion and 500 for yellow/blue confusion. Their results

Aéz§lestablished the general belief that color vision declined

 

 

W _l

K

continuguslvaith~age;_—nn attempt to duplicate this study,
but using more reliable instruments and controlling the
variables of intelligence, socio-economic status, education,
and occupation yielded conflicting results (Boice, Tinker,

and Paterson, 1948). The test showed only a 20% increase in

the post-60 age group, and there was no gradual decline with
W

 

age. Similar results were reported by Janouskova (1955).
This study also pointed out the importance of education
level: in the 60+ age group 18% with high level education

showed color blindness while 2 f the lgwlevel education

 

 

did so. By 1950 the use of the P.I.C. test was expanded to

‘v

study the relationship between age, visual acuity, and color
vision (Chapanis, 1950). The study was conducted at the
Baltimore Sesquicentennial Eghibition‘using a non-random

sample of 574 visitors, age 7-77. The author admits that

the test conditions were ot, dusty?)noisy3 and crowded.
l . .,-e ~xe-'

W

 

’-

. “##J.

Nevertheless, this is a highly popular study. Results indi-

cated that there was a curvilinear relationship between age
“’fl___,,.,i

94

and visual acuity; subjects under 15 and over 50 scoring
lower than the mid-years. Five different P.I.C. tests were
employed and indicated that there was a slight positive
/;5g__1elationship between color vision and age; There was no
evidence that score declined among elderly subjects. At

interface, there was a statistically significant positive

correlation betweerxi®nd ., but it was

slight. The author concluded that either there was no re-

lationship be:::::?gggilgcuity, and olor vision or that the

__‘_______‘
P.I.C. testsflwere too crude to detect it. Kleemeier (1955)

‘

argued with this conclusion. His results indicated that

 

visual acuity and color vision were related. He cautioned
\fl—fi—v
that visual acuity could be an intervening variable when

using P.I.C. tests.

As mentioned in Chapter 4, the P.I.C. tests are sus-
pect in their ability to measure age-related changes in
color vision. The conflicting evidence from available re-
search confirms this point. Nevertheless, it is a popular
test and frequently referenced in the less-scientific liter-

ature as a highly reliable indicator that color sensitivity

 

in general, and blue sensitivity specifically, diminish with

 

 

age. Lakowski (1958) compared data obtained on two anomalo-

 

scopes against P.I.C. tests and found that they agreed re-
garding general trends among age groups. But his data only
discriminated between color normals and extreme anomalies.

Deviants and color-weak were excluded from the study.

95

Perhaps the only reliable conclusion that can be made from
P.I.C. tests was made by Dalderup and Friedrichs (1969):
"Color sensitivity decreases with age, without a definite
preponderance of red-green over blue-yellow disturbances,

or vice versa" (p. 388).

Color Aptitude Tests

 

To date, very little research has been done on the
elderly using the<E:§;;> Gilbert (1957) applied the C.A.T.
to 355 subjects ages 10-93. All scores showed a slow rise

up to the age of 20 and, thereafter, a slow decline to the

oldest age. The most_£apid§degline\was in_thg§£i§§_gangg*.

[ééaS followed by green, yellow, and red. These results appear
to be as expected, but there is no other data with which to

compare it.

1......

I

Burnham and Clark (1955) studiedJcolormemory among

M

[3 subjects age 12-25. The results showe a gradual improvement

in ability. There were no data available regarding the
-’—~ /""‘~——.—-——~-~v-—._——--—:--
‘ "---- z;::—--'

elderly and color memory.

W

Conclusion

 

/' In summary, this chapter has been concerned with

studying the physiological characteristics of an aged visual

 

 

 

system and the potential and observed effects on color__

  
   

 

vision. The general conclusion from this information is

 

that there are degenerative changes and they do affect the
W JAV~ ~
elderly individual's perception of color. But it is this
W __4——-—-——/
author's contention that the information base is still too

 

96

scant to provide reliable indicators for the designer. We
_‘x

w

know that major degenerative changes in the pre-receptor

_/

 

 

\

elements affect light transmission and spectral sensitivity.

‘—

 

 

 

 

 

 

 

We do not know, however, if physiological changes in the

 

 

 

“-fi—‘Mnflm x 1".”-

/'
iKZ; _Mmreceptgrfilevel or neural pathway magnify these deficiencies

or if an adaptive process occurs that could compensate for
ire. _ii~fi~_w__mw~__

them. Furthermore, clinical assessments have provided only

 

 

an inconclusive, incomplete, and widely disparate body of
data concerning color perception. This is a result of
failure to clearly designate the parameters of elderly color
discrimination, the use of inappropriate testing procedures,
and inadequately controlled experiments. we know only that

_4

when compared with younger populations; the elderly_§gmer

times exhibit onfusionfltwee short and long
__J

wavelength hues. This confusion is exhibited predominately

 

 

m
at the blue and of the spectrum. We do not know, however,
. _ . ‘ —— \\
ޤ> how prevalent this is among the elderly as a unique popula-
W Av __ ___

 

 

‘
1
—-———

;L’ tion, or the actual parameters of the confusion. Available

data on color perception fail to clearly designate the

elderly's discrimination difficulties ir. v@ and

1v"

/

v”saturation differences.

 

//
,/we do not know how these difficulties may be dealt

with in agprosthetié'manner. Simply to avoid the use of

certain hue variations could result in a loss of some of the

informational character of the environment. We do not know

 

 

,'f color di ' ' ation difficulties may be compensated for
with variations in illumination, form, size, texture, or
-i_ fimflw,»w~- __. . _______ “njfih “fir, (,

 

97

distance from observer. Thus, the literature, to date, does
- -—--'-‘—‘—‘----“‘--- -.—._————-_~‘/

1
Imxnot provide sufficient practical information that could be

/ W '
/,.

applied to the use of color in the environment.
The designer is left to draw his/her own conclusions

as to appropriate color stimuli to facilitate a color coding
\M‘ ‘ 4/

stem in aidin th ' 'vidua1., It appears imperative

that future information be gathered from elderly populations

 

that would address the following issues:

- Can a color vision test be devised that would accur-
ately describe color discrimination ability among
hues, and the various values and saturations within
hues?

- Can such a test be devised to discriminate between
closely related hues, their values and saturations?

- Could this test be applied to an environmental situa-
tion under varying levels and types of illumination?

- Could test stimuli be varied in form, size, texture,
and distance from observer?

- Could this same test then be used to measure affect-
ive meaning in the environment? Ii\{(9

- Could the results of this test be assimilated_into

a model for use by the environmental designer?

~
.__1__ V_ —— %u_ _

-—_...... -—-.___‘. 7-- __

ii_.l_ _,__r,h‘m_fiuh*.#fif,,
Information provided by this type of testing would

enable the designer to approach the realm of color coding in

the geriatric institution with a firm scientific basis for

selection and use of color stimuli.

 

CHAPTER 6: CONCLUSION

The design process follows a general model of decision
-_ _____ “h - ——“\

making. ,Lang and Burnette (1924)\have outlined this process
: \wfiw H/

as shown in Figure 6.

INTEL'LIGENCE ——9 DEjIGN —r CHOICE —-9 IMPLEMENTATION —9 EVALUATION
l I

Figure 6: Model of the Decision Making Process
(Lang and Burnette, 1974)

The intelligence phase includes(gégégEEEE§§)and<3;£ihitib§:e£__’

the problem, analysis of the problem, and a synthesis °§_,.

 

 

m -
goals and objectigggfiin_§0lyigg the problem” The design

M -

‘fi— l_—u—
'fifim
#4“

phase provides for generating alternative solutions. The
choice and implementation phases involve selection of one of
the alternatives and seeing it through to realization. Eval-
uation, the final phase, is a rational examination of imple-
mentation relative to goals and objectives.

The purpose of this thesis has been to initiate the

W
decision making process for a design problem involving the

 

geriatric institution. And, it has examined that problem
within an Ecological framework. Two systems, the elderly
individual and the geriatric institution have been bounded
and an informational energy transfer at interface defined.
The elderly individual as a bounded system must be viewed

as a member of heterogeneous pulation conforming to a
\j‘w— 4.

developmental process known as aging. Aging is

 

 

98

fl

a»)

99

multi-dimensional, cumulative, and may result in decreased
competence in man/environment interaction. One aspect of

aging that may affect this interaction deals with the sys-

tem's ability to<gg;;;;;1and/EEEectflsfimuli) The visual
W

--'-I———

system has been considered by comparing the physiological
changes accompanying age to a normal visual network. It
has been found experimentally that the potential for degen-
erative changes in the pre-receptor elements of the eye

increase with age. Diminishing pupillary diameter, and

 

growth and chemical changes in the lens result inga decrease
/R in retinal illumination. Furthermore, spectral sensitivity
fl

1.

f

V

X.»

 

w
declines because ofGEEEEEEEEEEDandfiigggtflscatggg) Never-

theless, the extent to which these phenomena occur and are

characteristic of a normal aged visual system has yet to
be fully established. Psycho-physical research into color.
HwuHH~.afl_flflfl_fi_fl_fih____fifl_flfl__,ii

detection and discrimination ability has attempted to char-

__-_1...._...-.._._...- .— __ — —e , ~- — -__—.-.— "l- ._-‘-—.-..___
ifihmw - ‘1' “'-

EH

acterize the ontogenetic changes in color perception. It

has been demonstrated in this paper that such techniques
yield inconclusive and often contradictory results. This

results primarily because of the inability of available

W
methodology not only to establish age as a necessary and
.1i,“i~__‘___ ,#.______

 

 

sufficient condition for change, but also to characterize

\_ m— T... —-.__
——‘..—- \.._.~. .45....”

 

the\naturefiof th§19h§983.: The result is an overgeneraliza-
tion of competence level that leads to simplistic, prescrip-
tive methods for dealing with color as an environmental
stimulus for the elderly.

The environment as a bounded system has been construed

A

100

as the organization of material stimuli laden with informa-
tional resources for human use. The form and content of
that information may be manipulated in the design process
in order to enhance congruency between individual competence
and environmental press. In the geriatric institution it
has been suggested that envrionmental manipulation should
involve the use of a variety of stimuli to communicate a
single message. The role of individual stimuli and the
informational content that they possess, however, has not
been established in the literature. Furthermore, the rele-
vance of these stimuli to a geriatric user is, to date, a
field of virgin soil. It, therefore, has been the objective
of this paper to isolate a particular stimulus form, color,
and to identify its informational content in general, and
specifically to orientational cueing.

Color as an informational cue affects the human system

on three levels producing unconditioned) conditioned} and
7 . ““77 H m k“,

'reinforced/res onse . Extracting evidence from experimenta-

tion of these responses, it has been own that color does

,1”;— '” 1., "t‘r’fl
meet the necessary criteria as an(or1entat1onal ue. It
WM

eu—uflh-w

serves to delineate spatial form.via its alliance to edge
W

\

perception. Color provides focal points for the transfer of
\\,,.~_,__1_./1

meaningful information as shown in V13331_§EEEEE’£§§E§' And
finally, color provides reinforced responses to the affective
meaning of the behavior setting. Thus, as an isolated stimu-
lus, color provides orientational cueing in man/environment

interactions and should, therefore, be a viable tool in the

101

production of the environment. It must be re-

membered, however, that the prosthetic environment involves
the concomitant use of a variety of stimuli. Although it is
beyond the scope of this thesis, it is recommended that
similar analyses be conducted with other design elements

in order to establish individual roles, the relative contri—
bution of individual elements, and an hierarchial system for
their implementation. Only then may an- approach to
the prosthetic environment be accomplished.

Thus, the initial portion of the decision-making "_1,

_ _......-._*4_——-— -......._ _

 

_,___..,—.v-—-
¥

process has been completed in this paper. The design prob-

 

lem has been recognized and defined. It has been analyzed
through an in depth examination of the state of the art.

And finally, this paper has attempted to initiate the syn-

thesis portion of the intelligence phase by p3§i2g\potential"
research_qugggignsii It is obvious from this analysis of

the state of the art that before the designer may move con-
fidently to the design phase, further information is re-
quired. A considerable amount of statistically reliable
research needs to be done.

This thesis began with a series of general user re-
quirements that would apply to the use of color in a geria-
tric institution. They were generated in order to establish
a framework of design goals from which one could study the
literature. They provided a direction for the type of
information the designer needed in order to use color ef-

fectively in the institutional environment. In light of

102

the literature review done in this thesis, let us reexamine
M
these goals.

1) Color should faCilitate initial adaptation to the
W

 

institutional environment by providing information as to
the location and arrangement of objects and spaces, and
facilitate directionality in human movement. The literature
has indicated that color detection and edge perception are
concomitant processes following the same neural network
channel. Edge perception is known to facilitate feature
detection and, thus, the perception of form. Although fea-
ture detection is a refutable theory, it has been supported
by some psycho-physical research. If it is an acceptable
theory, then an orderly progression of color contrast should
facilitate orientation. But, we have noted that high con-
trast is undesirable from the user's standpoint. We do
not know, to date, how color contrasts may be devised to
facilitate edge perception and feature analysis for the
elderly user. Further information is required regarding the
interaction of color variations and edge detection, and how
those variations are to be organized. The primary concern
of the designer is, after all, the organizational process.
2) Color should fagilitatg_social_adaptation_hy;w,
providing information regarding behavior setting identifi-
cation. We owe a considerable debt for the work conducted
at G6tesburg using the semantic differential on the affec-
tive meanings of color. Isosemantic mapping of the color

solid has given the designer a considerable amount of

103

information regarding the cognitive and emotive processes
involved with behavior setting identification. This work is
still, however, in its very early stages. We need to know
considerably more information regarding the feature dimen-
sions and their parameters in colored environments. Fur-
thermore, there is a virtual void when it comes to identi-
fication of affective meanings of color to the geriatric
user. If there are some elements of color discrimination
confusion among the elderly, this may affect the meaning of
color to the individual. This issue clearly has not been
addressed in the literature, but is of considerable import-
ance in the design of behavior settings for the elderly.

3) Color should be used to provide complexity and _

variety in the environment in order to pose a degree of

M"

\_¥

challenge for maximizing human potential. The work at
thesburg has indicated that judged complexity was corre-
lated to chromatic strength. But user evaluation of an
environment employing strong colors noted that it assaulted
the senses. Clearly, a dichotomy has emerged. Furthermore,
there is no body of research that deals with the use of
color as a tool for challenge with any population, much less
the elderly. Does challenge imply that the environment
must be complex, or is color variation sufficient? This we
simply do not know. If variation is sufficient, we need to
know how the designer may build in a schedule of change to
be implemented by the institutional management with a mini-

mum of difficulty. It implies that the designer should be

104

prepared to provide a user guide. But until the designer
him/herself understands the process, such a guide will not
be forthcoming. Clearly, a model is required.

4) Color should provide an aesthetically pleasing

 

environment_ba§gg*on user preferences and values. It seems

 

unfair to impinge on basic human values by employing color
schemes that reflect current popular trends or magnify gen-
erational differences in color preference. To date, we
Ijé§2>know veryIlittlg\abgut~ge£iatricfgglor preferences, but
that information indicates that they prefer colors that
other elements in the literature suspect they have diffi-
culty in perceiving. Does the designer have the right or
responsibility to determine priorities of user needs and
values? This question cannot be addressed until we have
established a reliable body of information regarding both
color discrimination abilities and preferences. One would
suspect that once these aspects are clearly defined they

would probably be in agreement with one another, rather

than reflect their current apposition.

 

 

/ 5) Color should be selected relative to user capacity
f/jgiglo detect colorwstimuli. Chapter 5 dealt with this goal in

,. n—W'H-v n-.—§..-._‘ I _,.,,.....

detail. We need to know the parameters of elderly color
discrimination ability. To date, the literature has done
little more than provide a confusing picture that offers
little information of value. We need to know much more

precisely what the elderly perception of color is and what_r

 

‘xare the discrimination abilities_in_detecting_hue,

- .
_‘t tau/“q..- v ~~w~~w—n~W.—-Id_

.-

105

brightness, and saturation differences. Until such a knowl-
edge base exists, the designer can rely on little more than
intuition and artistic sensibility in selecting appropriate
colors for the institutional environment.

It would appear that the researcher attempting to
grapple with these problems could start with the develop-
ment of a color system for detecting discrimination ability
among the elderly. This system probably could be based on
an existing system such as Munsell or the Natural Color
System in order to facilitate model building. Laboratory
assessment of both sensitivity to and perception of the
system could be the next step. Then the system should be
applied to an environmental situation and reassessed for its
orientational cueing potential. Finally, a model could be
developed from.which the designer could predict the potential
of the system in a particular environmental situation. This
would allow the design phase to proceed by generating alter-
native solutions founded on a scientific data base rather
than intuition and generalization. The potential of color
as an orientational cueing mechanism in the geriatric insti-
tution provides a challenging and exciting avenue for future
environmental research. It is the fervent hope of this

author that these avenues be explored.

106

BIBL IOGRAP HY

Acking, C. and Kfiller, R., "The Perception of an Interior

as a Function of Its Color," Ergonomics, 15:4, 1972,

 

pp. 645-54.

Alvaro, M. B., "Senile Changes in the Crystalline Lens,"

Amer. J. Ophthal., 36, 1953, pp. 1241—1244.

Aurricchio, G. and Diotallevi, M., "Misura Della Secrezione
Dell'umore Acqueo Con La Tecnica Di Posengren Ed Ericson:
Sua Applicazione Nello Studio Della Fisiopatologia
Oculare," Ann. Ottal., 85, 1959, pp. 743-750 (in Weale,

1963).

Barker, R., "On the Nature of the Environment," J. of Social

 

Issues, 19, 1963, pp. 17-38.

Barraquer, I., Catarata Senil. Metodos Operatorios, Claraso,

Barcelona, 1924, (in Weale, 1963).

Becker, B., "The Decline in Aqueous Secretion and Outflow
Facility with Age," Amer. J. Ophthal., 1958, pp. 731-

736.

Bellows, J. G., Cataract and Anomalies of the Lens, Henry

Kimpton, London, 1944.

107

Berliner, M. L., Biomicroscopy of the Eye, Vol. II, Paul B.

Hoeber, Inc., New York, 1949.

Betteto, G., "Modificazioni Strutturali Dell-Arteria E Della
Vena Centrale Della Retina in Rapporto All'Accrescemento

Ed Alla Senescenza," Ann. Ottal., 79, 1953, pp. 79-92

 

(in Weale, 1963).

Birch, J., Private Communication. Report on Colour Vision
and Age to the Medical Research Council. 1964 (in

Ruddock, 1972).

Birren, James B., "The Special Senses and Perception," in
The Psychology of Aging, Birren, Prentice—Hall, New

Jersey, 1964, pp. 81-108.

Birren, J., Casperson, R., and Botwinick, J., "Age Changes

in Pupil Size," J. Geront., 5, 1950, pp. 216-221.

Blenker, M., "Environmental Change and the Aging Individual,"

The Geront., 7:2, Part I, 1967, pp. 49-52.

Boettner, E. A. and Wolter, J. R., "Transmission of the

Ocular Media," Invest. Ophthal., l, 1962, pp. 776-783.

Boles-Carenina, B., "Del Comportamento Del Sense Cromatico

In Relazione All'Eta," Ann. Ottal., 80, 1954, pp. 451-

 

458.

108

Boice, Mary, Tinker, Miles and Paterson, David, "Color Vision

and Age," Am. J. Psych., 61, 1948, pp. 520-6.

 

Burnham, R. W. and Clark, J. R., "A Test of Hue Memory,"

J. Appl. Psych., 39, 1955, pp. 164-172.

 

Chapanis, A., "Relationships Between Age, Visual Acuity and

Color Vision," Human Bio., 22, 1950, pp. 1-33.

 

Colavita, R. B., Sensory Changes in the Elderly, Charles C.

 

Thomas, Springfield, Illinois, 1978.

Cremer—Bartels, G., "fiber Das Vorkommen Lichtempfindlicher,
Fluorescierender Substanzen in Verschiedenen Geweben Von
Rinderaugen, Graefes Arch. Ophtal., 164, 1962, pp. 391-

398 (in Weale, 1963).

Davson, Hugh (Ed.), The eye, 2nd ed., Vol. I, Vegetative
Physiology and Biochemistry, Academic Press, New York,

1969.

Dalderup, L. M. and Friedrichs, M. L. C., "Colour Sensitivity

in Old Age," J. Amer. Ger. Soc., 17:4, 1969, pp. 388-390.

 

DeLong, Alton, "Coding Behavior and Levels of Cultural Inte-
gration: Synchronic and Diachronic Adaptive Mechanisms

in Human Organization," in EDRA II, Ed. Archea and

109

Eastman, Pittsburgh: Environmental Design Research

Association, 1970, pp. 354-63.

DeLong, Alton, "The Communication Process: A Generic Model

for Man-Environment Relations," Man-Environment Systems,

 

2:5, 1972, pp. 263-309.

DeLong, Alton, "Variability, Complexity, and Movement in

Environmental Communication," Arch. Design, Vol. 43,

 

1972, pp. 641-5.

DeLong, Alton, "Environments for the Elderly," J. of Comm.,

 

25:4, 1974, pp. 101-11.

Duverger, C. and Velter, B., Biomicroscopye Du Cristallin,

Masson Et Cie, Paris, 1930 (in Weale, 1963).

Ericksen, C., "Object Location in a Complex Perceptual Field,"

J. Exp. Psych., 45, 1953, pp. 126-32.

 

Fisher, F. P., In Modern Trends in Ophthamology, Vol. II,

A. Sorsby, Butterworth and Co., London, 1948.

Geist, Harold, Psychological Aspects of the Aging Process:

With Sociolggical Implications, Warren Green, Inc., 1968.

 

Gerard, R. M., "Color and Emotional Arousal," Am. Psych.,

 

13:340, 1958.

110

Gilbert, J., "Age Changes in Color Matching," J. Geront.,

 

123:2, 1957, pp. 210-15.

Gilchrist, A., "The Perception of Surface Blacks and

Whites," Sci. Am., 240:3, 1979, pp. 112-25.

Goldmann, H., "Studien fiber Die Alterskernstreifen Der

Linse," Arch. Augenheilk., 110, 1937, pp. 405-414.

 

Goldmann, H., "Senile Changes of the Lens and the Vitreous,"

Am. J. Ophthal., 57, 1964, pp. 1-12.

 

Graham, M., "Health Facilities: Color Them Caring," NBS

Publ. 516, 1978, pp. 9-12.

 

Gustafson, C., "A Method of Estimating Surface Color Dis-
criminability for Coding Training Equipment and Predicting

Label Legibility," USAF-WADD Tech. Note, 1960, pp. 60-83.

Hall, E. T., The Hidden Dimension, Doubleday and Co., Inc.,

 

Garden City, New York, 1969.

Ham, A. W., Histology, 6th ed., J. B. Lippincott Co.,

 

Philadelphia, 1979.

Hecht, S., Schlaer, S., and Pirenne, M., "Energy, Quanta,

and Vision," J. Gen. Phys., 25, 1942, pp. 819-40.

 

lll

Hess, C., Gr. Saemisch Handb. Augenheilk, 3rd ed., 1911

 

(in Weale, 1963).

Hogan, M. J. and Zimmerman, L. E., Ophthalmic Pathology,

 

2nd ed., W. B. Saunders, London, 1962.

Hubel, D. and Wiesel, T., "Integrative Action in the Lateral

Geniculate Body," J. Physiol., 155, 1961, pp. 385-98.

 

Hurvich, L. and Jameson, D., "An Opponant Process Theory

of Color Vision," Psychol. Rev., 64, 1957, pp. 384-404.

 

Jacobs, R. and Krohn, D., "Variations in Fluorescence
Characteristics of Intact Human Crystalline Lens Seg-

ments as a Function of Age," J. Geront., 31:6, 1976,

 

pp. 641—647.

Jameson, D. and Hurvich, L., "Perceived Color and its De-
pendence on Focal, Surrounding, and Preceding Stimulus

Variables," J. Op. Soc. Amer., 49, 1959, pp. 890-98.

 

Janisse, M. P., Pupillometry, The Psychology of the Pupil-

lary Resppnse, Wiley & Sons, Inc., New York, 1977.

 

Janouskova, K., "Color Vision and Age," Ophthal. Lit., 9:134,

1955, p. 48, (M. Klima-Trans.).

Jones, M., "Color Coding," Human Factors, Dec., 1962, pp. 355-

 

65.

 

112

Katz, D., The World of Color, Trans. R. B. Macleod and

 

C. W. Fox, Kegan Paul, London, 1935.

Katz, D., "Color Preferences in the Insane," J. of Abnormal

 

and Social Psych., 26, 1931, pp. 203-9.

 

Kauffman, Lloyd, Sight and Mind, Oxford University Press,

 

New York, 1974.

Kleemeier, R., "The Relationship Between Ortho-Rator Tests
of Acuity and Color Vision in a Senescent Group," g;_

Appl. Psychol., 36, 1952, pp. 114-16.

 

Koff, T., "Natural Overview of the Elderly Population," J;

of Arch. Ed., 31:1, 1977, pp. 5-8.

 

Krause, A. C., "The Chemistry of the Lens IV the Nature of

the Lenticular Proteins," Am. J. Ophthal., 17, 1934,

 

pp. 502—14.

Kuffler, 8., "Discharge Patterns and Functional Organization

on Mammalian Retina," J. Neurophysiol., 16, 1953, pp.

 

37-68.

Kumnick, L. 5., "Aging and the Efficiency of the Pupillary

Mechanism," J. Geront., 11, 2, 1956, pp. 160-164.

 

113

Lakowski, R., :Age and Colour Vision," Advancement of

 

Science, 15, 1958, pp. 231-6.

Lakowski, R., "Theory and Practice of Color Vision Testing:

A Review," Part I, British J. of Ind. Med., 26, 1969,

 

pp. 173-89.

Land, B., "The Retinex Theory of Color Vision," Sci. Am.,

237:6, 1977, pp. 108-128.

Lang, J. and Burnette, C., "AmModel of the Process," in

#-

 

;\Designingfor Human Behavior, ds. Lang, Burnette,
\ _____
Moleski, and Vachon, Dowden, Hutchinson, & Ross Publ.,

1974, pp. 43-51.

Laszlo, E., "System Structure and Experience: Toward a

Scientific Theory of the Mind," in Current TOpics in

 

Contemporary Thought, Gordon and Breach Science Publ.,

 

New York, 1969.

Lawton, M., "Public Behavior of Older People in Congregate
Housing," EDRA II, Archea and Eastman (Eds.), Dowden,

Hutchinson and Ross, Publ., Stroudsberg, PA., 1973.

Lawton, M. Powell, "An Ecological Theory of Aging Applied
to Elderly Housing," J. of Arch. Ed., 31:1, 1977,

pp. 8-10.

114

Lawton, M. and Simon, B., "The Ecology of Social Relation-

ships in Housing for the Elderly," The Geront., 8:2,

 

1968, pp. 108-15.

Lebensohn, J. E., "Biochemistry of the Lens," Arch. Ophthal.,

 

15, 1936, pp. 216-221.

Leinhos, R., "Die Altersabhangigkeit Des Augenpupilnendurch-

messers," Optik., 16, 1959, pp. 669-671 (in Weale, 1963).

Lindsley, 0., "Geriatric Behavior Prosthetics," in New

Thoughts on Old Age, Kastenbaum (Ed.), Springer Publ.,

 

New York, 1964, pp. 41-60.

Lowry, O. H. and Hastings, H. B., "Quantitative Histochemical

Changes on Aging," in Cowdry's Problems on Aging, Ed.

 

A. I. Lansing, Williams and Wilkins Co., Baltimore, 1972.

Mather, J., Stare, C., and Breinin, 8., "Color Preferences

in a Geriatric Population," The Geront., Winter 1971:1,

 

pp. 311-13.

Maurice, D. M., "The Structure and Transparency of the

Cornea," J. Physiol., (London), 136, 1957, pp. 263-286.

 

McFarland, R. A., Domey, R. G., Warren, A. B., and Ward, D.C.,
"Dark Adaptation as a Function of Age: I. A. Statistical

Analysis," J. Geront., 15, 1960, pp. 149-154.

 

115

Millodot, Michael, "The Influence of Age on the Chromatic

Aberration of the ye," Graefes Arch. Ophthal., Springer-

 

Verlag, 198, 1976, pp. 235-243.

Mok, C. C. and Waley, S. G., "N-Terminal Groups of Lens

Proteins," Expl. Eye Res., 7, 1968, pp. 148-153.

 

Morgon, G., Goodson, F., and Jones, T., "Age Differences in
the Associations Between the Felt Temperatures and

Color Choices," Am. J. Psych., 88:1, 1976, pp. 125-30.

 

Neugarten, B., Middle Age and Aging, The University of Chicago

 

Press, Chicago, Illinois, 1968.

Nourse, J. and Welch, R., "Emotional Attributes of Color: A

Comparison of Violet and Green," Perceptual and Motor

 

Skills, 32, 1971, pp. 403-6.

Padgem, C. and Saunders, J., The Perception of Light and

 

Color, Bell and Sons, Ltd., London, 1975.

Pastalan, Leon, Personal Communication, 1979.

Pastalan, L., Mautz, R. and Merrill, J., "The Simulation
of Age-Related Sensory Losses: A New Approach to the
Study of Environmental Barriers," in EDRA I, Ed.

Wolfgang Preiser, Pittsburgh, 1973, Mimeograph.

 

116

Pastalan, Leon, "How the Elderly Negotiate Their Environ-

ment," A paper prepared for the Environment for the Aged

 

Conference, San Juan, Puerto Rico, Dec. 17-20, 1971.

Payne, M., "Color as an Independent Variable in Perceptual

Research," Psych. Bull., 61:3, 1964, pp. 199-208.

 

Perin, C., With Man in Mind, The MIT Press, Cambridge, Mass.,

 

1970.

Piaget, J., and Inhelder, B., The Child's Concept of Space,

 

Routledge and Kegan Paul, London, 1956.

Pike, K., Language in Relation to a Unified Theory of the

 

Structure of Human Behavior, Mouton & Co., The Hague,

 

1967.

Promisel, D., "Visual Target Location as a Function of

Number and Kind of Competing Signals," J. Appl. Psych.,

 

45, 1961, pp. 420-27.

Rapoport, Amos, "An Anthropoligical Approach to Environ—

mental Design Research," in Responding to Social Change,

 

Eds. Basil Honikman, Dowden, Hutchinson, and Ross, Inc.,

Stroudsberg, PA., 1975.

Robertson, G. W. and Yudkin, J., "Effect of Age Upon Dark

Adaptation," J. Physiol., 103, 1944, pp. 108.

 

117

Ruddock, K. H., "Light Transmission Through the Ocular
Media and Macular Pigment and its Significance for

Psychophysical Investigation," Reprint Handbook of

 

Sensory Physiology, Vol. Vii/4, 1972.

 

Ruddock, K. H., "The Effect of Age Upon Colour Vision-I:
Response in the Receptoral System of the Human Eye,"

Vision Res., 5, 1965, pp. 37-45.

 

Ruddock, K. H., "The Effect of Age Upon Colour Vision-II:
Changes with Age in Light Transmission of the Ocular

Media," Vision Res., 5, 1965, pp. 47-58.

 

Rushton, W., "Visual Pigments in Man," Sci. Am., 205, 1962,

pp. 120-132.

Said, F. S. and Weale, R. A., "The Variation with Age of the
Spectral Transmissivity of the Living Crystalline Lens,"

Gerontolggia, 3, 1959, pp. 213-231.

 

Salmony, D., Private Communication, 1961 (in Weale, 1963).

Shale, K. and Gribbin, K., "Adult Development and Aging,"

in Aging: Scientific Perspectives and Social Issues,

 

Schwartz (Ed.) Van Nostrand, Publ., New York, 1975,

pp. 65-96.

118

Schale, K. and Hess, R., Color and Personality, Grune &

 

Stratton, New York, 1963.

Schwartz, A. and Proppe, H., "Toward Person/Environment

Transactional Research in Aging," The Geront., 10:4,

 

1970, pp. 228-32.

Smith, H., "Age Differences in Color Discrimination," J;

Gen. Psych., 29, 1943, pp. 191-226.

 

Smith, P., "On the Growth of the Crystalline Lens," Trans.

Ophthal. Soc. U.K., 3, 1883, pp. 79-99.

 

Snyder, Lorraine, "An Exploratory Study of Patterns of
Social Interaction, Organization, and Facility Design

in Three Nursing Homes," Int'l. J. Aging and Human Dev.,

 

4:4, 1973, pp. 319-33.

Sommer, Robert, "Small Group Ecology in Institutions for

the Elderly," in Spatial Behavior of the Elderly,

 

Pastalan and Carson, University of Michigan Press,

1970, pp. 25-39.

Spector, A., Freund, I. and Augusteyn, R., "Age-Dependent
Changes in the Structure of Alpha-Crystalline," Invest.

Ophthal., 10, 1971, pp. 677-686.

119

Stiles, W. S. and Burch, S. M., "N.P.L. Color-Matching

Investigation: Final Report," Optica Acta, 6, 1959,

 

pp. 1-26.

Stordant, Martha, "Recognition Across Visual Fields and

Age," J. Geront., 27:4, 1972, pp. 482-6.

 

Studer, Raymond, "The Organization of Spatial Stimuli," in

Spatial Behavior of Older People, Patalan and Carson,

 

University of Michigan Press, 1970, pp. 102-23.

Surwillo, Walter, "Choice Reaction Time and Speed of Infor-

mation Processing in Old Age," Perceptual and Motor

 

Skills, 36:1, pp. 321-2.

Tiffin, Joseph and Kuhn, Hedwig, "Color Discrimination in

Industry," Archives of Ophthal., 28, 1942, pp. 851-9.

 

Verriest, G., Valdevyvere, R., and Vanderonck, R., "Varia-

tions De La Discrimination Chromatique," Rev. Opt., 41,

 

1962, pp. 499-509.

Vogt, A. and Lfissi, U., "Weitere Untersuchungen Uber Das
Relief Der Menschlichen Linsenkernoberflache," Graefes

Arch. Ophthal., 100, 1919, pp. 157-167.

 

120

Wagner, H., MacNichol, E., and Wolbarsht, M., "The Res-
ponse Properties of Single Ganglion Cells in the

Goldfish Retina," J. Gen. Physiol., 43, 1960, pp. 45-

 

62.

Wald, G., "The Photo Chemistry of Vision," Documental

 

Ophthal., 3, 1949, pp. 94-137.

Wallace, J. G., "Some Studies of Perception in Relation to

Age," British J. of Psych., 47, 1956, pp. 283-97.

 

Weale, R., The AgingyEye, Hoeber Medical Division Harper

 

& Row Publ., New York, 1963.

Wells, N., "A Description of the Affective Character of the

Colors of the Spectrum," The Psych. Bull., 7:6, 1910,

 

pp. 181-95.

Wienke, R. E., "Refractive Error and the Red/Green Ratio,"

J. Opt. Soc. Am., 50, 1960, pp. 341-42.

 

Wolf, E. and Gardiner, J. 8., "Studies on the Scatter of
Light in the Dioptric Media of the Eye as a Basis of

Visual Glare," Arch. Ophthal., 74, 1965, pp. 338-345.

 

Wright, B. and Rainwater, L., "The Meanings of Color,"

J. Gen. Psych., 67, 1962, pp. 89-99.