A COMPARISON OF msnmnomnzm AND N-ON- msn‘rummuzm MENTALLY RETARDED cmwm my mTELLEcmALLv NORMAL CHILDREN ON | :NBiDENTAL AND ‘INTENTIONAL LEARNING msxs , Thesis for the ‘Degrée of Ph. D. ‘ f , ' MICHIGAN STATE umvzrzsm ,BARRY mamas ‘ 1970 1 , _ . - -- - .' 1. ‘3 LIBRARY ” ‘ kw". ’ '71 ' ‘. t" .h - ‘H ' s , - ,,‘ l‘Vthhlf '34“ C "3:" .' v_ f a 0‘ F H“ k. .. . g v r " ‘ .. ‘ TV." This is to certify that the thesis entitled A COMPARISON OF INSTITUTIONALIZED AND NON- INSTITUTIONALIZED MENTALLY RETARDED CHILDREN AND INTELLECTUALLY NORMAL CHILDREN ON INCIDENTAL AND INTENTIONAL LEARNING TASKS presented by Barry Mintzes has been accepted towards fulfillment of the requirements for Ph.D. degree in Education Date 5/8/70 0-169 ABSTRACT A COMPARISON OF INSTITUTIONALIZED AND NON-INSTITUTIONALIZED MENTALLY RETARDED CHILDREN AND INTELLECTUALLY NORMAL CHILDREN ON INCIDENTAL AND INTENTIONAL LEARNING TASKS By Barry Mintzes The present study was conducted in order to determine whether or not the retarded are deficient in their ability to learn incidentally. The study involved 1”“ subjects, 72 of whom were institutionalized and 72 of whom were not. Of these groups of 72, 2” were retarded, 2A were normals matched to the retarded group on chronological age, and 2A were normals matched to the retarded group on mental age. Within each group of 2M, 12 received an intentional task and 12 received an incidental task. The tasks were exactly the same with the exception of the instructions. The tasks consisted of the subjects being shown 10 series' of figures. The end figure in each series was similar to but significantly different from the others. In the incidental task the subject was merely instructed at the beginning of the first series of figures to watch what the experimenter does. In the intentional task, the subject, in addition to being instructed to watch what the experimenter does, was also instructed to pay attention as the experimenter made the last figure in each series different. After a three minute intermediary task the subjects were tested for their recall of the changes made in each series of figures. It was found that institutionalized retardates were deficient in their ability to learn incidentally when compared to normals while the same was not true for non-institutionalized retardates. It was also found that institutionalized retardates were also deficient in their ability to learn inten— tionally and this was the result of a LOW-MA-LOW-IQ deficit. Non-institutionalized retardates were not significantly different from non-institutionalized normals in their ability to learn intentionally. Finally, subjects, in general, receiving the intentional task performed significantly better than subjects receiving the incidental task. A COMPARISON OF INSTITUTIONALIZED AND NON-INSTITUTIONALIZED MENTALLY RETARDED CHILDREN AND INTELLECTUALLY NORMAL CHILDREN ON INCIDENTAL AND INTENTIONAL LEARNING TASKS By Barry Mintzes A THESIS Submitted to Michigan State University in partial fulfillment of the requirements ‘ for the degree of DOCTOR OF PHILOSOPHY Department of Counseling, Personnel Services and Educational Psychology College of Education 1970 ACKNOWLEDGEMENTS The author wishes to pay tribute to the following people who all contributed in some way to the successful completion of this dissertation: Dr. James Engelkes, who served not only as the author's major professor, but as a friend also, giving freely of his time when the author most needed it and remained flexible so as to enable the author to make the most out of his program; Dr. M. R. Denny, who provided the author with the original idea for this study and gave a great deal of his time during the initial stages when the pilot study was being done and the groundwork was being laid; Dr. Gregory Miller and Dr. Clessen Martin, members of his doctoral committee who helped to improve the final quality of this dissertation; Sister Honora, Director of Social Services, and Miss Ruth Jaffee, social worker, both of St. Francis Home for Boys, Detroit, Michigan, who made the data collection there a very pleasant task by their tremendous help and cooperation; Mr. Tom Shriver, Chief Psychologist, Lapeer State Training Home, Lapeer, Michigan, who helped the author 11 considerably in getting the project approved by the institution as well as arranging the subjects to be tested; Dr. Paul Spata, Superintendent, Mr. Dale Shears, Chief Psychologist, Mr. Don Church, Director of Clinical Services, all of Boys Training School, Lansing, Michigan, and Mr. Ron Fine, Director of Research, Department of Social Services, State of Michigan, all of whom made possible the collection of the data at Boys Training School; Mr. Bob Beauchamp, Superintendent of Schools, Ovid-Elsie Area Schools, Elsie, Michigan, who gave the author permission to use his school district for the present study; Mr. Case, Principal, Ovid Junior High School, Mr. Leonard, Principal, Ovid North Elementary School, and Mr. Lentz, Principal, Ovid-Elsie High School, all of whom were of great help to the author in placing the resources of their respective schools at his hands; Bob Wilson, who gave the author a tremendous amount of time and assistance in making sense out of an otherwise complicated design and an unfathomable computer system;' David R. Walters, the author's closest friend in the doctoral program whose constant companionship for two years helped make tolerable an otherwise difficult and anxiety ridden program; 111 Richard Gay, Arthur Dell Orto, Kenneth LaFleur, John Dahm, David Stugart, Richard Darnell, Ben Perri, David Cabush, Willie Williams, Errol Freschette, and Frank Johnson, fellow doctoral students whose association the author enjoyed immensely; Carol Anne, the author's loving wife who was a constant source of support and encouragement and had to endure an inordinate amount of hardship and strain throughout. iv TABLE OF CONTENTS Page ACKNOWLEDGMENTS . . . . . . . . . . . . ' 11 LIST OF TABLES . . . . . . . . . . . . v1 LIST OF FIGURES . . . . . . . . . . . . vii LIST OF APPENDICES . . . . . . . . . . . viii Chapter I. INTRODUCTION. - . . . . . . . . . 1 Introductory Statement. . . . . . . 1 Statement of the Problem . . . . . . A Hypotheses. . . . . . . . . . 5 Need for the Study . . . . . . . . 5 Definition of Terms. . . . . . . 8 II. REVIEW OF THE LITERATURE. . . . . . . 9 General Research on Learning in the Retarded. . . . . 9 Attempts to Apply Learning Theory to Mental Retardation . . . . . 12 Theoretical Basis for Incidental Learning. . . . . . . . . 18 Research on Incidental Learning in the Retardate . . . . . . . . . . 22 III. METHODOLOGY . . . . . . . . . . . 27 Subjects . . . . . . . . . 27 Materials and Procedures . . . . . . 29 Study Design and Analyses. . . . . . 32 IV. RESULTS . . . . . . . . . . . . 34 V. DISCUSSION . . . . . . . . . . . 47 Limitations of the Study . . . . . . 53 Implications for Further Research . . . 5U Summary. . . . . . . . . . . . 55 REFERENCES 0 0 O O O O O O O O O O O O 57 APPENDICES. . . . . . . . . . . . . . 60 Tables 1. LIST OF TABLES Means and standard deviations for institu- tionalized and non-institutionalized mentally retarded subjects and intellectually normal subjects on recall acores for incidental and intentional learning tasks. . . . . . . Analysis of variance of recall scores for institutionalized mentally retarded subjects and intellectually normal subjects on an incidental learning task . . . . . . . T-tests analyzing the differences between the three types of institutionalized groups on the incidental learning task . . . . . . Analysis of variance of recall scores for institutionalized mentally retarded subjects and intellectually normal subjects on an intentional learning task . . . . . . . T-tests analyzing the differences between the three types of institutionalized groups on the intentional learning task. . . . . . Analysis of variance of recall scores for non-institutionalized mentally retarded sub- jects and intellectually normal children on an incidental learning task . . . . . . Analysis of variance of recall scores for non-institutionalized mentally retarded sub— jects and intellectually normal subjects on an intentibnal learning'task . . . . . . Analysis of variance of recall scores for institutionalized and non—institutionalized mentally retarded and intellectually normal subjects on incidental and intentional learning tasks. . . . . . . . . . . vi Page 35 37 37 39 39 HO ”0 U2 Figure LIST OF FIGURES Page Graphic representation of the interaction between type of group (ret., older normal, younger normal) and type of treatment (intent., incident) . . . . . . . . . 43 Graphic representation of the interaction between institutional dimension (inst. and non-inst.) and type of group (ret., older normal, younger normal). . . . . . . . NU vii LIST OF APPENDICES Appendix A. Means and standard deviations for institu— tionalized and non-institutionalized mentally retarded subjects and intellec- tually normal subjects on chronological age for incidental and intentional learn- ing tasks (in years). . . . . . . . Means and standard deviations for institu- tionalized and non-institutionalized mentally retarded subjects and intellec- tually normal subjects on mental age for incidental and intentional learning tasks (in years) . . . . . . . . . . . Means and standard deviations for institu- tionalized and non-institutionalized mentally retarded subjects and intellec- tually normal subjects on intelligence quotient for incidental and intentional learning tasks. . . . . . . . . . Means and standard deviations for institu— tionalized mentally retarded subjects and intellectually normal subjects on years institutionalized for incidental and intentional learning tasks (in years) . . Raw data for institutionalized mentally retarded and intellectually normal chil- dren on incidental and intentional learn- ing task recall scores . . . . . . . Raw data for non-institutionalized mentally retarded and intellectually normal children on incidental and inten- tional learning task recall scores . . . viii Page 61 62 63 6h 65 66 CHAPTER I INTRODUCTION Introductory Statement In recent years, a great deal has been written about the mentally retarded. Numerous definitions have been offered, various causes of retardation have been discussed and many comparisons have been drawn between retarded and normal individuals. There are many ways in which the retarded are different from normals. The retarded frequently have concomitant physical problems which are associated with impaired cerebral functioning. Among these may be visual problems, epilepsy, cerebral palsy, speech handicaps, hearing problems and numerous others. Psychological problems are also a concern, especially with regard to their self concept, family relationships, and peer relationships. Social factors also pose certain problems for the retarded, especially with regard to their functioning in the world of work, being a productive member of the community, and facing a fair degree of prejudice from others in the community. It is in the area of educational and vocational training, however, that the retarded probably face the greatest number of problems. It is here that they seem most obviously I different. In comparing a normal person of a given chronological age with a retarded person of the same chronological age, there is generally an obvious difference in terms of what the two are able to learn or comprehend. If one even looks only at the very name given to the disability, namely, "mental retardation", it seems obvious that something is amiss with regard to the mental development of the retarded individual. What necessarily follows from this as the obvious charac- teristic that would stand out is their differential ability to learn. The retarded just do not seem to be able to grasp facts, concepts, and ideas as quickly as normals. As a result, researchers in the field have attempted to take what is known about the nature of the learning process in normals, and apply it to the retarded in hopes of gaining a better understanding into the nature of specific ways in which the retarded are indeed deficient in their abilities to learn. Since there are varying degrees of mental retar- dation, it would seem worthwhile at this point to discuss how the IQ range used in the present study was derived. The American Association on Mental Deficiency classifies the degrees of retardation as follows: Category Binet IQ Wechsler IQ Profound Below 20 Below 25 Severe 2O - 35 25 - 39 Moderate 36 - 51 HO - SH Mild 52 - 67 55 - 69 Borderline 68 - 83 70 - 8H This study focused essentially on those classified as mild and borderline. These individuals are the ones who can benefit from vocational training and can often be a self-supporting unskilled or semi-skilled employee. Some borderlines can even live and function independently in the community. Furthermore, these two groups together are the most representative of the retarded in that they comprise approximately 90% of all those afflicted with mental retardation in the United States. This group is also frequently referred to as educable mentally retarded, the IQ range for which is generally given as 50 - 75. Since it is apparent that there is much variation in classifying the mentally retarded, the present study did not refer to any specific categories. In order to include, however, all those considered to be retarded, yet capable of educational and vocational training, an IQ range of 50 - 85 was established for the purpose of defining the group of mentally retarded individuals to whom all references in this study was made. Statement of the Problem This investigation focused specifically on the incidental learning deficit which has been hypothesized to account for the inability of the retarded to learn as well as normals. It has been said that one of the reasons why the retarded do not learn as well as normals is because they do not pick up on cues that are not directly involved in the learning task at hand. Their attention must be specifically directed to whatever it is they are supposed to learn. Normals will generally learn a great deal just from interacting with their environment. This is especially important before one begins formal schooling. Throughout the course of any day in a child's life there are countless numbers of stimuli impinging upon his receptors. Although, for the most part, nobody is directing him to learn anything specifically, he is nevertheless absorbing, storing, assimilating, and integrating the diverse bits of information with which he is coming into contact. This is not the case, however, with the retarded person. He typically.does not pick up most of this information unless his attention is specifically called to it. This puts him at a considerable disadvantage when he begins his formal schooling. While the normal child will have a backlog of events to draw upon in school, the retarded child often does not and consequently falls even further behind. One question this raises is that of whether or not the retarded child would be able to learn as well as the normal child on intentional learning tasks. These would be tasks where both the retarded and normals would be tested on materials to which their attention had been called. Hypotheses The present study investigated the following hypotheses: 1. When attention is called to the stimulus object there will be no significant difference between normals and retardates on the mean number of items recalled correctly. 2. When no attention is called to the stimulus object, normals will have a significantly higher recall rate than the retardates. Need for the Study In order to help retarded individuals get the greatest possible benefit out of their formal education or vocational training, it is necessary to have a good understanding of the ways in which they learn. In order to improve teaching and training methods, however, it is also necessary to be aware of the ways in which they are deficient in learning. Once aware of what these learning deficiencies are, corrective methods can be instituted in an attempt to provide the maximum possible conditions in which learning may occur. The present study is important in that it attempted to shed further light on a specific way in which retarded individuals are felt to be deficient in their abilities to learn, namely, with regard to incidental learning. To begin with, very few studies have been done investigating whether or not an incidental learning deficit does, indeed, exist in the retarded. In addition, that which is felt to be incidental learning in the present study is different from the kinds of incidental learning that have been researched in other studies. The kind of incidental learning investigated here is that which the author feels is more typical of the way it occurs in actual situations. With the sole exception of the passive incidental task in Singer's (1963) study, every incidental learning task used by every previous experimenter has provided the subject with a set to respond though usually to a stimulus other than the one on which they will later be tested. It is felt that the passive incidental learning task which Singer used is more in keeping with the true nature of incidental learning as originally postulated by Denny (1964). This is confirmed by an example which Denny used to describe this deficit (Denny, 1966) wherein he referred to the passive incidental task in Singer's research, as well as in numerous recent personal communications with Dr. Denny. This study attempted to seek further evidence of the existence of an incidental learning deficit among the retarded by using a passive incidental task only, so that at no time during the presentation of the task was the subject provided with a set to learn. Even in Singer's (1963) research, the passive incidental task was presented after the active incidental task and so the subject already had a set to respond since he was asked specific questions during the active task. This study was an attempt to eliminate the possible confounding variable of response set when viewing incidental learning. If we are saying that mentally retarded individuals are poorer performers because they are poorer incidental learners than normals, and further that consistent responding is necessary for incidental learning to take place, then we must provide a situation where we have not already begun to direct the subject to respond. In Benoit's framework the retardate tends to be a stimulus bound organism responding to the stimulus of the moment rather than maintaining internal stimuli or sets. Thus, to evaluate the incidental learning deficit it is important to make sure that no internal sets to respond are set up by the experimental procedure as has typically been the case. Definition of Terms Incidental Learning The ability of an organism to respond to a stimulus when no attention is called to it. Intentional Learning The ability of an organism to respond to a stimulus when attention is called to it. Response to a Stimulus The accuracy of recall of the stimulus presented last in each series. Mental Retardation According to the American Association on Mental Deficiency "Mental retardation refers to subaverage general intellectual functioning which originates during the developmental period and is associated with impairment in adaptive behavior". The mentally retarded individual suffers from the disability known as mental retardation. He will be referred to as a MR. This study focused essentially on those MR's with IQ's from 50 - 85. Normal This refers to individuals not diagnosed as mentally retarded and having an IQ from 90 - llO. CHAPTER II REVIEW OF THE LITERATURE General Research on Learning F“ in the Retarded The last decade has witnessed a marked increase in . w .1-l,.‘-L'_ ._.-. the amount of research devoted to studying the learning . ' " .I'."_ deficiencies of mental retardates. McPherson (19N8) was able to list only a dozen studies devoted to a consid- eration of learning in mentally defective individuals. In a later study, he was only able to find twenty-eight articles on the subject between 190A and 1958 (McPherson, 1961). Stolurow (1958) has stated how it is a strange paradox that while in the past fifty years there has been a considerable expansion in the psychology of learning, hardly any attempt at all had been made to understand the learning process of the mentally retarded or how they differ in learning ability from other children. More recently, however, an increased fre- quency of research has been appearing in the literature touching on virtually every area and aspect of learning as it relates to the retarded. Even so, however, Denny (l96h) in his review of research in learning and performance on the retarded reports, "Data on learning 10 in the mentally retarded are not abundant, but the studies that have been done suggest that this is a field of great potential interest". He further suggests that because of this, little of a definitive nature can be said about learning in the retarded. A fairly common observation concerning the abilities and skills of the retarded is that they inevitably learn more slowly and retain less than normal individuals. Educational programs have thus been developed on the assumption that the learning deficit experienced by the retarded is general and univariate, that is, he lacks "intelligence". The retardate is generally assumed to be inferior to the normal individual in all aspects of the learning process and it is also assumed that what- ever may be causing the difficulty in one area is responsible for inferior performance in other areas. As a result, special education programs have generally consisted of providing the retarded individual with essentially the same materials in the same manner as is given to the normal individual, but in lesser amounts and at a slower rate. Available research, however, suggests that the learning deficiency of mildly and moderately retarded persons is task-specific or related only to certain aspects of the learning situation. There is even some evidence to suggest that under certain conditions the ll learning and retention of retardates are comparable to normals. This will be discussed later on in the chapter. One might question whether distractability or poor retention represents a significant source of inferiority. Does the problem lie in inferior verbal mediation, per- ceptual difficulty, or poor discrimination? By the same token, however, there is an optimistic side to the problem. If we have a better understanding of the circumstances in which a retarded child performs better we may have uncovered a more effective means of educating and training him. If we are aware of the specific deficits in a given case, we may be able to either eliminate the deficit or create conditions such that the deficit will not interfere with learning. Robinson and Robinson (1965) report, "Detailed investigations of the learning of retarded children can answer a number of questions which are extremely relevant to understanding the basic kinds of handicaps from which they suffer, to planning their educational experiences, and to predicting the sorts of tasks which they can do more or less well". Mental retardation cannot be considered a general and unitary behavioral deficit. Rather, the mental retardate is one whose interaction with his environment is impaired in specific and special ways. The research evidence suggests that learning disability associated with mental deficiency is specific to particular processes 12 and tasks. Identification of such impairments, and the conditions under which they are available, is necessary for the development of efficient and effective training methods (Baumeister, 1968). Attempts to Apply Learninngheory to Mental Retardation Although there are large areas of agreement among psychologists who have proposed theories to explain the manner in which organisms learn, there are also heated disagreements. Up to this time, however, few of the theoretical controversies have been especially relevant to studies which have been carried out with retarded children (Robinson & Robinson, 1964). It has been fairly recent, in fact, that even the agreed-upon aspects have been recognized to have implications for understanding the field of mental retardation. When existing research designs have been extended to retarded subjects, the general laws of learning have almost invariably been demonstrated to apply to them as well as to other organisms. In other words, studies with retarded children have lent confirmation to the accumulated evidence about the ways in which organisms acquire new behavioral patterns (Robinson & Robinson, 1965). The learning phenomena reviewed by Robinson and Robinson include such concepts as the shape of the 13 learning curve, short-term retention, classical con- ditioning, operant conditioning, discrimination learning, stimulus generalization, paired-associate learning, and learning set. Baumeister (1968) reports, "Very few attempts have been made to formulate theories of behavior to account specifically for the inadequacies characteristic of retarded individuals". In a review, (Zeaman, 1959) and in a theoretical article (Zeaman & House, 1963) attempts have been made to analyze the learning deficits of mental retardates in terms of an attentional model of discrimination learning. Their basic notion is that a chain of two fundamental processes underlies discrimination learning: (1) observing the various stimulus dimensions, and (2) making the instru— mental response. By the term "dimensions", House and Zeaman are referring to broad classes of "cues" that have in common a stimulus property. Thus, color is a dimension while the specific colors are cues. The basic problem for the retardate is a low initial probability of attending to the relevant dimensions. The retardate's capacity to acquire an instrumental response is not in question, but rather his ability to attend to the relevant and critical stimulus dimensions that lead to making the appropriate discriminations. House and Zeaman point out, rather convincingly, that slow discrimination learning is not characterized by a low I“ rate of improvement in performance, but rather by the amount of time and practice needed for the learning to start (i.e., retardates experience relatively less difficulty in learning than in starting). They have offered some suggestions, based on their theory and research, for improving retardates' performance on discrimination learning tasks. Since they regard as the retardates' fundamental difficulty his inability to attend to the relevant stimulus dimensions, the remedial procedure is to increase the probability that he will observe the relevant dimensions. Another theoretical point of view that has been focused upon the learning and retention disabilities associated with mental retardation involves the stimulus trace concept developed by Ellis (Ellis, 1963). Two major constructs are proposed to account specifically for short-term memory deficits in the retardate, stimulus trace and nervous system integrity. Ellis' notion of stimulus trace is roughly analagous to the reverberating circuit of neurophysiology. A stimulus, impinging upon a receptor organ, produces certain changes in the activity of the central nervous system. These electrical changes outlast the duration of the stimulus that initiated them, apparently by reverberating temporarily over various sequences of neurons . 15 The construct of central nervous system integrity is less well defined by Ellis. By this concept he is evidently referring to the comparative ability of an organism to maintain the trace. Thus, the retardate, by fault of "neuropathology" suffers impairment in his ability to maintain an adequate trace with respect to duration or amplitude. To the extent that learning and long—term memory are dependent upon consolidation of the trace, the organism with a debilitated central nervous system will be impaired in these functions as well. Ellis views the noncontinuity of events to be associated as crucial to an explanation of learning and retention deficits in the retarded (i.e., if A and B are to be associated but are temporally separated, then strictly speaking B is associated with the trace of A). If Ellis' analysis of mental deficiency in relation to short-term memory is correct, the best approach to training retarded individuals requires that effective measures be undertaken to improve their short-term memory. It does not seem likely that one can act directly upon the retardate to improve his ability to maintain a trace. Rather, the approach would be to arrange his environment to compensate for his inferior and impoverished trace. 16 The Russian theory of learning in the retardates, best expounded by Luria is known as verbal dysfunction theory and views mental retardation as the consequence of nervous system pathology around which learning occurs (Ellis, 1963). According to Luria's theory, two primary signal systems subserve higher nervous activity. One of these systems is governed by direct signals from the envir- onment and is characterized by its reflexive nature. The second signal system, possessing the properties of abstraction and conceptualization, involves language. This latter system develops to regulate responses to the direct signals. Thus the human subordinates his behavior to his "verbally formulated intentions". Verbal behavior in the normally functioning individual is pre-eminent over motor behavior. The retardate is characterized by a pathological weakness of these basic processes and thus acquires connections more slowly, will respond inappropriately, and will be easily disrupted by extraneous stimuli and fatigue. While the mentally retarded do not appear to be able, in general, to learn as well as normals (slower learning and poorer short-term retention [Ellis, 1963]) one must also keep in mind that there are a number of responses which the retarded can sometimes learn almost as well as normals of the same chronological age. Along 17 similar lines, Denny (1964) has shoWn that there is little available evidence of an appreciable deficit in long-term retention when the mentally retarded are compared with normals, provided the two are matched on original learning. That is, both normals and retarded have learned the same amount of material initially. On the other hand, the MR's clearly exhibit a (number of deficits which relate both to learning and general functioning (Denny, 1966). One of the most basic deficits seems to involve duration of attention (Zeaman & House, 1963; Denny, 196“). Referring to this attention deficit Denny reports "PreSumably the retarded lack the self initiated sets which typically make for consistent and continued responding in the normal", (Denny, 1966). The retarded also tend to be more stimulus bound than the normal--"more at the beck and call of each and every stimulus change" (Denny, 196”). As a result of this attention deficit a special kind of incidental learning deficit occurs. Denny continues, "When the mentally retarded are sufficiently well instructed or guided, as under intentional learning conditions, they often do not show a learning deficit. But when retarded children are unwittingly posed with a learning task which is not only incidental but requires responding to the same set of stimuli for ten to fifteen 18 seconds before the critical item appears and becomes learnable, then they show a marked deficit, whereas object or color identification which can be learned incidentally with a single glance may not show any deficit at all" (Denny, 1966). Support has been found for this in research done by Singer (1963). In summary, it has only been in the past decade that research into learning principles and their application to the mentally retarded has received serious attention. Furthermore, most of the research that has been done has focused upon the usual areas of learning such as paired-associates, verbal mediation, classical and instrumental conditioning, etc. In addition, only a sparse number of attempts have been made to develop theories applicable to the learning deficits characteristic of defective individuals. In examining the ways in which the retarded are indeed deficient in their abilities to learn, Denny has postulated the existence of an incidental learning deficit, an area which had been researched before with normals (Jenkins, 1933; Saltzman & Atkinson, 195“; Brown, 195"; Gleitman and Kamsin, 1957; and Neimark & Saltzman, 1953), but never with retardates. Theoretical Basis for Incidental Learning The original hypothesis that mental retardates are poorer performers because they are poorer incidental l9 learners than normals was first set forth by Denny (196A). In developing this hypothesis he was greatly influenced by the work of Benoit (1957) who has applied Hebb's theory of Behavior (Hebb, 19u9) to mental retardation. Like Gestalt theory, Hebb's highly theoretical notions about the functions of the central nervous system begin with perceptual behavior but there the resemblance ends. Hebb's entire theory concerns the transmission of electrical impulses from one part of the nervous system to another over pathways which become increasingly integrated in the course of experience as they are used over and over in an orderly fashion. Hebb proposes that when a particular set of sensations is experienced over and over, some of the cortical cells within the brain begin to be organized into a simple corresponding functional unit called a "cell assembly". Hebb post- ulated that when particular combinations of cell assemblies are simultaneously fired over and over, they come to be integrated into increasingly complex functional units. The functional unit next larger than the cell assembly Hebb termed a "phase sequence". Benoit, using Hebb's theory as a basis, states that the retardate is deficient in integrative sets and phase sequences. He translates this into practice by showing how in a general way it has implications for training the retarded. Hebb's emphasis on the 20 importance of attention, for example, suggests that it is imperative that the stimulus field be arranged so that the child's attention is focused on the material to be learned. A further aspect of Benoit's analysis is that the retardate is a stimulus bound concrete organism. Singer (1963) claims that this stimulus bound characteristic of the retarded is well known and is often used as a diagnostic indicator by those who work with the mentally retarded. This stimulus bound quality of the retardate reflects his tendency to respond to the stimuli of the moment and an inability to maintain internal stimuli or sets. This stimulus bound characteristic is an important factor for learning in the framework of elicitation theory (Denny & Adelman, 1955). They report "For all practical purposes, learning occurs if and only if a response is elicited in a consistent manner. By consistent we refer to whether or not the response is elicited each time the stimulus is presented; the more often a response is elicited each timethe stimulus is presented the more consistent the elicitation". In other words, according to elicitation theory, the organism must be made to respond consistently to changes in stimuli in order to be able to differentiate them. Singer (1963) states, "The retardate often responds differently to the same stimulus, and the same way to 21 different stimuli. And if the retarded child will not respond consistently or repeatedly in an ordinary situation little incidental learning will take place. We would expect little consistent responding because the retardate is bound to the fleeting stimulus of the moment and cannot maintain an internal set". What this means is that the retardate is unable to maintain a set to respond. His attention must be directed by another person as he will very rarely respond on his own. Response here need not mean any more than recognizing or becoming aware of something. In summary then, from elicitation theory it follows that the retarded child who, in a typical situation is unable to respond consistently to the same stimulus fails to learn incidentally that which the normal child does. Since during the first few years of life most of the learning which takes place is not intentional but rather incidental, the retarded child does not respond to all of the cues in the environment that the normal child is aware of and thus is already behind at the time when formal schooling begins. By consistent responding to stimuli the normal child builds up a good background of data upon which to build when the directed learning tasks begin in grade school. The retarded child, however, does not incidentally acquire this background .m‘wfi 22 information and hence begins at an initial disadvantage from which he never recovers. Research on Incidental Learning in the Retardate Most of the research that has been done with the retarded has focused on directed learning tasks (also referred to as intentional learning tasks) and has failed to show consistent differences between normals and retardates. Very little research, however, has been done to investigate the difference between the two groups on incidental learning tasks. The first of these studies was done by Goldstein and Kass (1961) who studied incidental learning in retarded (mean CA 10.3 years, mean IQ 72) and gifted children (mean CA n.8, mean IQ 136). They used a picture of a street scene with several numbers incor- porated such as car licenses, street numbers, etc. The subjects were told to locate the numbers and were later tested for what they learned of the scene. Goldstein and Kass found no difference between the groups on the intentional learning task or the inci- dental learning task. In another study, Hetherington and Banta (1952) used colored pictures of common objects mounted on five by seven inch cards. The subjects were a normal group (mean IQ 101), an organic retarded group (mean 23 IQ 60, mean CA 118 months), and a nonorganic retarded group (mean IQ 60, with a mean CA of 120 months). In their incidental task each subject named the color of the object on the card as it was presented and after an exposure to the series of fifteen cards, he was given five minutes to name as many of the objects as he could. The intentional task consisted of presenting a similar series of fifteen cards and to instruct the subject to remember as many of the objects as he could. The subject was then given five minutes to recall as many of the objects as he could. It was shown that non- institutionalized educable organics manifested a significant incidental learning deficit when compared with normals (p < .01), whereas educable familials did not. On intentional learning of the object-picture material, the differences among all three groups were not statistically significant (p < .01). Baumeister (1963) attempted to compare normals and retardates, matched on the basis of CA, with respect to incidental learning and retention. In the intentional learning situation, each subject was shown ten pictures, one at a time, of common objects with the instructions to remember the objects. Subjects in the incidental learning task were shown the same pictures, but instructed to remember the colors of the objects. All subjects were given a free recall test 2A on the names of the objects immediately after the ten pictures had been presented. Following a A8 hour period, recognition tests were administered in which the subject selected the original picture when presented along with three distractors. The results indicated that the normals performed significantly better on both immediate recall tests (p < .05). After the AB hour period, the groups were equal on the recognition test of the incidental material. However, in retention of intentional learning, the retardates were superior (p < .01). It was suggested that the learning deficit in the mentally retarded is; task specific. Oliver (1963) attempted to determine whether or not there was a difference between educable mentally retarded children and intellectually normal children in their responses on an incidental learning task. In the intentional task the subjects were instructed to observe and remember the stimulus material presented. In the incidental task the subjects were engaged in an orienting task which directed their attention to the stimulus material but did not require their remembering or learning it. Retention was assessed immediately and after a 2A hour period. Oliver found that the mentally retarded subjects did not differ significantly from the intellectually normal subjects of the same 25 mental age or same chronological age in the ability to learn incidentally. This finding was present for both immediate and delayed recall performance. Also, the retarded subjects and subjects of chronological ages 10 - 12 learned significantly more under intentional learning conditions than they did under incidental learning conditions. This finding was present for immediate recall performance only. Normal subjects of chronological ages 6 - 9 duplicated the above finding for both immediate and delayed recall performance. Intellectually normal subjects of differing chronological ages did not demonstrate a significant difference in their performance under incidental learning conditions. This result was present for both immediate and delayed recall. Intellectually normal subjects of differing chronological ages did not demonstrate a significant difference in their performance under intentional learning conditions. This finding was present for both immediate and delayed recall. All subjects in this study, under incidental learning conditions, demonstrated a significant loss in retention during the 2“ hours that elapsed between the two testing periods. 3 Singer (1963) investigated three types of incidental learning presumably of different degrees of difficulty in younger and older normal and younger and older retarded children. A test of intentional learning was also given. 26 The active incidental task involved the subject playing a game and then answering questions about what transpired. The passive incidental task, and the most difficult of the three, involved the subject watching the experimenter draw some designs, and answering questions about what transpired. The misdirected incidental task consisted of the subject naming objects of doll furniture and later being asked what color the objects were. It was found that on the CA match, the retarded subjects were signif- icantly poorer incidental learners than the normals (p < .001), but on the MA match, there were no signif- icant differences between the retarded and the normals on incidental learning for both the younger and older groups. No significant differences were found between any of the groups on the intentional learning task. In summary, it is apparent that at best what little research has been done investigating the existence of an incidental learning deficit in the retarded, has yielded conflicting evidence. Where there does seem to be uniformity of opinion, however, is on the intentional learning tasks, the retarded and the normals not being found to differ significantly. In addition, incidental learning has been looked at in a number of different ways each changing the meaning of the concept slightly. Hence there has not even been uniformity of opinion regarding what constitutes incidental learning. CHAPTER III METHODOLOGY Subjects The present study contains 12 groups of 12 subjects each for a total of 1AA subjects. Of these 1“", 72 were institutionalized and 72 came from the public schools. Within each group of 72, there were three subgroups of 2“ each. One subgroup contained retarded subjects with a mean chronological age of approximately 15 1/2 years, while the other two subgroups contained normal subjects, one matched with the retarded subgroup on chronological age, the other matched with the retarded subgroup on mental age. Within each subgroup, 12 subjects received the intentional learning task while the other 12 received the incidental learning task. Subjects were randomly assigned to treatment conditions and were also randomly tested so that there was no particular order regarding how many consecutive times a given task was given within a subgroup. The retarded subjects were selected randomly from among all those at the institution or school having an IQ between 50-85 and falling between the ages of 13-17. 27 28 The normal subjects were selected in a similar fashion from among all those having an IQ between 90—110 and falling between the ages of either 13-17 or 8-12. 1 .The institutionalized retardates came from Lapeer State Training Home, Lapeer, Michigan, the older institutionalized normals came from Boys Training School, Lt.".ru-AW ll.- _ l, E Lansing, Michigan, and the younger institutionalized normals came from St. Francis Home for Boys, Detroit, Michigan. All of the non-institutionalized subjects came from the Ovid-Elsie school system in Ovid, Michigan, and Elsie, Michigan. Since both Sarason (1953) as well as Spitz (195“), among others have raised questions concerning the possible detrimental effects of institutionalization upon children it was felt that some control for this variable was in order. This was the reason for using both an institutionalized as well as a non-institutionalized sample. Those selected for the institutionalized sample had to have been living in the institution for at least six months immediately prior to the study in order to be included in the population from which the random sample was drawn. Since Hetherington and Banta (1962) found that organic retardates performed significantly more poorly than familial retardates on an incidental learning task, 29 the case histories of each retarded subject was reviewed. A subject with any mention of organic brain damage as part of the etiology was automatically eliminated from the study. Therefore, only the familial retardates were the MR subjects in the present investigation. Materials and Procedures The materials for the incidental and intentional tasks were exactly the same. They consisted of different series' of patterns which the experimenter (E) drew with pencil and paper while the subject (S) passively watched. The basic idea for the patterns presented to the subjects was derived largely from the patterns used by Singer (1963) in his passive incidental task. A number of the patterns used here are identical to some that Singer used. Essentially, the patterns were derived on the basis of their simplicity, and ease of making one similar to but significantly different from the others in the series. While Singer used 7 series' of patterns, he had a number of other tasks to fill up the subjects' time before they had to recall the changes made in the last figure of each series. In the present investigation, 10 series' of patterns were chosen largely on the basis of a pilot study done beforehand which indicated that by giving this many a better spread on the recall scores could be obtained. This was much 30 more important in the present study since the recall period was only three minutes while in Singer's study it was much longer as a result of the other tasks the subject had to complete before being asked to recall the changes in the passive incidental task. The following series' of patterns were presented. Each series required approximately ten seconds to draw. The end figure in each series was slightly different from the preceding figures in the same series. 1.oooooooooo(3 2.66666 66660 ////////// /‘ ZSZSAIAMAZBZSAIA.A.A MM! 1: xxxxxxxxx ® ‘ IO i) :3 i) :‘O l—J Only the procedures varied slightly. For the incidental task, just prior to the presentation of the first series of patterns, the following instructions were given, "Now watch what I do". Nothing more was then said by E until after the last series of patterns was presented. At that time 31 the intermediary task was presented. This was true for both the normal and retarded subjects. For the intentional task, just prior to the presentation of the first series of patterns, the following instructions were given, "Now watch what I do". As in the incidental task, these instructions were not repeated. In the intentional task, however, at the end of each series, during the presentation of the last figure (the odd one), the following instructions were given, "Now watch what I'm doing to this one", thereby calling attention to the change. This was true for both normal and retarded subjects. After the subject was shown all ten series' of patterns, an unrelated task (intermediary task) was presented to him to use up exactly three minutes before testing him on recall. This was found to be necessary as a result of the pilot study in order to get a better spread on the recall scores. This task consisted of presenting S with an inverted L-shaped figure III. S was asked to close his eyes while E guided his hand with a pencil in it up through the figure 25 times. E then removed the figure, asked S to open his eyes, and presented him with a T-shaped figure a]: . S was then instructed to start at the bottom and draw a line up through it. He was also instructed to turn and continue all the way to one of the ends. This was to 32 see whether or not 8 would draw his line the same way in which his hand was forced by E in the L-shaped figure. This had nothing to do with the experiment and no hypotheses were offered regarding this. Upon concluding this task, S was tested for his recall of the odd figures drawn at the end of each series with which he was presented. For each series, E drew one of the figures for S and said, "Remember when I drew these?" "What did I do to one of them?" "Tell me or show me". If S indicated correctly what the change was he received a score of one. If he indicated that he did not remember what the change was or indicated the change incorrectly, he received a score of zero. All S's received a score based on the number of items recalled correctly out of the ten series' presented. Hence, the highest score one could receive was ten; the lowest, zero. StudygDesign and Analyses The primary goal of this study was to determine whether or not the retarded subjects would indeed show themselves to be deficient in their abilities to learn incidentally when compared with groups of normal subjects. A secondary goal of the study was to deter- mine whether or not the retarded subjects could learn as well as the normals on an intentional learning task. 33 In order to examine the results of the data, the design used was a three dimensional model which was completely crossed and balanced. The independent variables were as follows: I - Institutionalization I Institutionalized l I Non-institutionalized 2 G - Type of subject G MR - CA 13-17, IQ 50-85 1 G2 Normals - CA 13-17, IQ 90—110 G3 Normals - CA 8-12, IQ 90-110 T - Treatment Tl Intentional learning task T2 Incidental learning task The dependent variable was the number recalled correctly by each subject. The data was analyzed by a three-way analysis of variance as performed by the FACREP routine of the AOV program on the Control Data Corporation 3600 computer at the Michigan State University Computer Center. Scheffe post-hoe comparisons were also made where there were significant main effects. Since this was a fixed effects model, generalizations are necessarily limited to the levels of the independent variables (Hays, 1963). CHAPTER IV RESULTS This chapter will present the results of the data collected in order to examine the hypotheses under investigation. The two hypotheses predicted that on incidental learning, retardates would do worse than normals, while on intentional learning there would be no differences between the groups. Appendices A - D provide a complete breakdown for the reader of the means and standard deviations of chronological ages, mental ages, IQs, and years institutionalized for all groups and treatments. Table 1 presents how each of the groups compared on the dependent variable, namely, recall scores. It can be seen that the institutionalized group of retardates (IlGl) did worse than any of the other groups in the study on both the intentional (T1) and the incidental (T2) learning tasks with their worst performance being on the incidental task. The row means indicated that the older normals had the best performance. The older institu- tionalized normals (Ile) ranked first on recall scores on the intentional task and third on recall scores on 34 35 Hw.m mm.m mm.m mo.m memes Cezaoo mfilm «o nw.m em.m oo.m fined mm.m mm.a mm.m mm.H mo.m m oaalom 0H A 0v mHmEnoz . walma <0 w>.m mm.H wo.> mm.H mw.© mm.H mm.m NH.H mm.> m oaalom 0H . . A 0V meEhoz eauma ac mwlom 0H av eeeeeeem ee.H mm.m mm.H mw.: Ll’\ \0 No.3 oe.H mm.m oe.H o H A meme: .o.m see: .e.m see: .a.m eeez .o.m ewe: 30m . “Nev HepeeeaeeH Afiev HeeofiecmseH Amev HeeemeaeeH AHBV HeeoaeeeeeH ANHV pmmfiamcoauSpApmcchoz AHHV eeNHHmCOHpSDHpmcH .mxmmp wcficnmcfi HmCOHpeeucfi new Henceeflocfi pom menoom . Hamomn co mpomwSSm Hmenoc mafimzpoefiampcfi new muconQSm weenmpee maawucme emmaamcoHuSDHpmcfiucoc new eoNfiHwCOAuSpHpmcH pom mcofipmfi>ce onmecmpm use mcmmzll.H mqm ~05 N-S. 38 difference, however, between the older normals and the younger normals. Table A shows the results of the analysis of variance which was done comparing the institutionalized retardates and normals on the intentional learning task. A signif— icant F-ratio was also obtained here (p < .01). Table 5 presents the results of t-tests based on the findings reported in Table A. It can be seen here that on intentional learning the retardates performed signif- icantly worse than the older normals (p < .01). The younger normals, however, also did significantly worse on intentional learning than did the older normals (p < .05). There was no difference between retardates and younger normals. Thus, the older normal group performed significantly better than both the younger normal group and the retarded group. Table 6 shows the results of the analysis of variance which was done comparing the non-institutionalized retardates and normals on incidental learning. This resulted in a non-significant F—ratio indicating no differences between the non-institutionalized groups on incidental learning. Table 7 shows the results of the analysis of variance which was done comparing the non-institution- alized retardates and normals on intentional learning. This also resulted in a non—significant F-ratio 39 TABLE A.--Analysis of variance of recall scores for institutionalized mentally retarded subjects and intellectually normal subjects on an intentional learning task. Source of Sum of Mean Variance Squares d'f’ Square F Significance Between 37.50 2- 18.75 10.08 p < .01 Within 61.25 33 1.86 Total 98.75 35 TABLE 5.--T-tests analyzing the differences between the three types of institutionalized groups on the intentional learning task. Comparison Difference T-value Significance Retardates vs. older normals ”2'50 5°00 D < .01 Retardates vs. _ r younger normals 1‘23 1.8M p > .05 N.S. Older normals vs. younger normals +l‘25 2-15 P < ~05 DO TABLE 6.--Analysis of variance of recall scores for non- institutionalized mentally retarded subjects and intellectually normal children on an incidental learning task. cu“ x _.Y__ Source of Sum of Mean F Variance Squares d’f' Square Significance Between 27.55 2 13.78 3.26 p > .05 N.S. Within 139.67 33 “.23 Total 167.22 35 TABLE 7.--Ana1ysis of variance of recall scores for non- institutionalized mentally retarded subjects and intellectually normal subjects on an intentional learning task. ‘“ Source of Sum of Mean Variance Squares 'f° Square F Significance Between 5.39 2 2.70 .90 p > .05 N.S. Within 98.92 33 3.00 Total lON.3l 35 A1 indicating no differences between the non-institutionalized groups on intentional learning. Table 8 shows the results of the overall three-way analysis of variance. The finding of importance here with regard to the incidental learning deficit theory is the lack of a significant interaction between type of group and type of treatment (GT) which is graphically illus- trated in Figure 1. This tells us that the differences found within the retarded groups on incidental vs. intentional learning was not significantly greater than the differences found within either of the normal groups. Other findings of interest in Table 8 include the fact that there was a significant main effect for type of treatment (T). Inspection of the data indicates that subjects, in general, who received the intentional task did better than subjects who received the incidental task. Also of interest here is the lack of a signif- icant main effect for the institutional dimension (1), but a significant interaction between the institutional dimension and type of group (IG) was found. This is graphically represented in Figure 2. What this tells us is that while institutionalization, in general, did not play a significant role in learning, the combination of what group one was in and whether or not he was institutionalized did make a difference. 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Hmepoz . walma <0 ma.mm no.5 mm.ooa :m.m nm.mm N:.m ma.xo no.0 mm.wm QHHIom 0H Hmegoz NHImH <0 mm.m0 mH.w 00.0w Nw.w om.mm wo.m mm.L0 mm.w mm.mm mwlom 0H eoenmpom mecca son .0.m cmoz .0.m can: .0.m new: .0.m can: mom came tempo HmpcoefiocH choaucopeH HmpcmefloeH HMCOHpcmch emeaflecoaeeuaemcHaeoz eemflfiaeoneSpapmeH .mxmm» wcacnmoa HmCOHpcooCH 0cm HmpcoeHoCH L00 pcofiuozv oocowfiaaopcfi co mpoonQSm Hmesoc mafimspooaaopcfl 02m muoowQSm emenmpop hHHmpcmE UmNHHwCOHQSUprCHICOC GEM UGNHHmCOHpSpprCH LOW mCOHVMH>®U Uhmficmpm Ucw mcmmEll.O NHszmm< 6N APPENDIX D.-—Means and standard deviations for institution- alized mentally retarded subjects and intellectually normal subjects on years institutionalized for incidental and intentional learning tasks (in years). Intentional Incidental Grand mean . for Mean S.D. Mean S.D. row means Retarded IQ 50-85 2.66 2.09 5.58 2.25 A.12 CA 13-17 Normal IQ 90-110 .91 .15 1.25 .6h 1.08 CA 13—17 Normal IQ 90-110 1.08 .55 1.58 1.0A 1.33 CA 8-12 Grand mean for column 1.55 2.47 means APPENDIX E.--Raw data for institutionalized mentally retarded and intellectually normal children on incidental and intentional learning task recall scores. Intentional Incidental Subject # Recall Score Subject # Recall Score 1 . g 2 2 5 ' 3 A 3 A A 3 Retarded A 7 5 2 IQ 50-85 2 fi 6 7 CA 13-17 7 5 g g 8 5 9 6 9 3 10 u 10 1 ll 5 11 3 12_ 5 l2 2 l 7 1 9 2 7 2 5 3 7 3 7 Normal A 6 A 5 IQ 90-110 2 3 2 3 CA 13-17 7 7 7 9 8 6 8 A 9 9 9 6 10 9 10 5 11 8 11 6 12 6 12 6 l 6 1 6 2 6 2 7 3 5 3 A Normal A 8 A 8 IQ 90-110 2 g 2 g CA 8-12 7 8 7 9 8 6 8 7 9 3 9 7 10 7 10 5 11 5 11 5 12 8 l2 6 66 APPENDIX F.--Raw data for non-institutionalized mentally retarded and intellectually normal children on incidental and intentional learning task recall scores. Intentional Incidental Subject # Recall Score Subject # Recall Score 1 6 1 8 2 7 2 3 3 9 3 6 Retarded A 9 A 8 IQ 50-85 2 g 2 fl CA 13-17 7 5 7 5 8 7 8 u 9 5 9 7 10 3 10 6 11 7 11 5 12 7 12 A l 6 l 8 2 6 2 6 3 3 3 7 Normal A 6 A 8 IQ 90-110 6 g 2 8 CA 13-17 7 A 7 3 ' 8 6 8 5 9 9 9 7 10 10 10 7 11 8 ll 8 l2 7 12 9 1 7 1 2 2 7 2 7 3 5 3 A Normal A 5 A 7 IQ 90-110 2 g 2 7 CA 8-12 7 A 7 7 8 A 8 5 9 8 9 2 10 5 10 9 ll 5 11 A 12 7 12 A