A DESCRIPTIVE STUDY OF WOLOF MOTHER-CHILD MUTUAL GAZE INTERACTIONS IN RURAL SENEGAL AND THEIR ASSOCIATIONS WITH CHILD LANGUAGE SKILLS. By Yatma Diop A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of Human Development and Family Studies — Master of Science 2018 ABSTRACT By Yatma Diop A DESCRIPTIVE STUDY OF WOLOF MOTHER-CHILD MUTUAL GAZE INTERACTIONS IN RURAL SENEGAL AND THEIR ASSOCIATIONS WITH CHILD LANGUAGE SKILLS. The importance of mutual gaze in mother-child relationships and in the language development of children is well documented in Western societies, but it is not known whether mutual gaze between mothers and infants is equally important in Africa. In the present study, the frequency, duration, and nature of mutual gaze interactions were observed between caregivers and children living in Wolof-speaking communities in rural Senegal. Relations between mother-child mutual gaze and Wolof children’s language skills were also examined. Caregivers (n = 60), and their children (age range: 20-30 months) were observed as they played together and their interactions videorecorded and coded. The Wolof versions of the CDI and language milestones parent reports of child language, were administered. Descriptive analyses of 5-min face-to-face interactions revealed that rural Senegalese mothers looked their children in the eye over 13 times with an average total duration of over 25 sec. Mothers were the major initiators of the mutual gaze episodes, which were predominantly positive in nature, but they also demonstrated a high degree of responsiveness to children’s bids for mutual gaze. Separate linear regressions showed that mutual gaze frequency significantly predicted Wolof children’s vocabulary, but not their language milestones. Although some research suggests that eye gaze might be culturally stigmatized, results suggest that mothers use this approach frequently when interacting with their young children. It is also evident that mutual gaze can be important in helping Wolof children learn their mother tongue. ACKNOWLEDGEMENTS I would like to express my sincere gratitude to my advisor Dr. Lori Skibbe for supervising my work with patience, and for providing me with invaluable advice and skills during my two-year master’s program. To my committee members, who have provided guidance and advice throughout the research process. I am grateful to all the ELLI lab members, for their wonderful feedback during my presentations. My heartfelt thanks go to Drs. Anne Fernald, Ann Weber, Virginia Marchman, and to all the research team at the Language Learning Lab at Stanford University, for our longstanding collaborations. I thank the Fulbright program for funding my master’s program at Michigan State University. Finally, I would like to acknowledge my wife Ndeye Sokhna Dia for being patient and for taking care of our little baby Mouhameth Diop in Senegal during the time I was in the US to complete the M.A. program at M.S.U. iii TABLE OF CONTENTS LIST OF TABLES ..................................................................................................................... vi LIST OF FIGURES .................................................................................................................. vii INTRODUCTION ...................................................................................................................... 1 ARGUMENT FOR STUDYING MUTUAL GAZE AND CHILD LANGUAGE IN SENEGAL 5 RESEARCH AIMS AND HYPOTHESES ............................................................................... 10 METHODS ............................................................................................................................... 11 Participants ........................................................................................................................... 11 Measures and procedures ...................................................................................................... 11 Measures of Gaze and procedures ................................................................................ 11 Leader and Emotional context ...................................................................................... 12 Measures of child language outcomes .......................................................................... 13 RESULTS................................................................................................................................. 16 Descriptive results ................................................................................................................. 16 Mutual gaze frequency ................................................................................................. 16 Gaze duration ............................................................................................................... 16 Nature of mutual gaze .................................................................................................. 16 Mothers’ responsiveness when children initiate mutual gaze ........................................ 17 Relations between mother-child mutual gaze and child language .......................................... 17 Correlations ................................................................................................................. 17 Regression analyses ..................................................................................................... 17 DISCUSSION ........................................................................................................................... 19 Explanation of the findings .................................................................................................. 19 Implications of the study and directions for future research .................................................. 24 Limitations ........................................................................................................................... 24 iv CONCLUSION ........................................................................................................................ 26 APPENDICES .......................................................................................................................... 27 Appendix 1: Tables ............................................................................................................... 28 Appendix 2: Figures .............................................................................................................. 29 REFERENCES ......................................................................................................................... 31 v LIST OF TABLES Table 1: Correlations between Mutual Gaze Measures ............................................................. 28 Table 2: Summary of linear regressions with CDI scores as the outcome (N = 60) .................... 28 Table 3: Summary linear regression with Language Milestones scores as the outcome (N = 60) ................................................................................................................................................. 28 vi LIST OF FIGURES Figure 1: Frequency distribution of mutual gaze instances ........................................................ 29 Figure 2: Distribution of total gaze duration ............................................................................. 29 Figure 3: Emotional Context ................................................................................................... 30 Figure 4: Mutual Gaze initiation .............................................................................................. 30 vii INTRODUCTION A variety of studies have looked at how parent-child interactions can promote children’s language skills (Weber, Fernald & Diop, 2017; Rowe, 2012). But, the majority of research on the verbal and nonverbal aspects of interactions that support early word learning has been done in western societies. Studies conducted in these societies propose that mutual gaze plays a foundational role for the development of children’s language because it is a way by which children learn more sophisticated gaze skills which help children to navigate their environments (Brooks & Meltzoff, 2008; Csibra & Gergely, 2009). The present study has two goals. The first goal is to give a picture of how Senegalese rural mothers interact with their children through mutual gaze. The second goal is to investigate whether children’s language development relates to the amount of mutual gaze that mothers and children use during their interactions. In Western societies, many studies have shown that maternal responsiveness is important for children’s outcomes. A responsive caregiver is one who shows appropriate reactions to children in the context of daily exchanges (Bornstein et al., 2008). However, it is important to note that some studies found differences in maternal responsiveness across cultures (Broesch et al., 2016), so appropriate reactions to children’s needs may be culturally bound. In general, there exist different types of responsiveness depending on the type of behavior that the mother or the caregiver is responding to (e.g., signs of discomfort, verbal overture, and facial expressions). Responsiveness also follows three steps: the first one is observation, when the caregiver or the mother pays attention to particular signs of need from the child; the second step is interpretation, when the caregiver accurately interprets the child needs. The last step is the action that the caregiver makes in order to meet the child’s needs with consistency and efficiency (Eshel, Daelmans, Mello & Martines, 2006). Responsive parenting is particularly critical for children 1 from infancy through 5 years of age. Children who are not generally exposed to consistently high levels of maternal responsiveness have lower scores on measures of language, cognition, and social development (Landry et al., 2001). Maternal responsiveness supports children’s development in a number of important ways. Maternal responsiveness is associated with later literacy outcomes (Taylor, Anthony, Aghara, Smith, & Landry, 2008) and children’s social-emotional competence (Denham, 1993). In particular, maternal responsiveness predicts children’s language outcomes in early childhood. A study investigating the effects of maternal responsiveness on children’s early language milestones found that, at 9 and 13 months, maternal responsiveness was a good predictor of several child language milestones: first imitation, first words in expressive language, first word combinations, and first use of language to talk about the past (Tamis-LeMonda, Bornstein, & Baumwell, 2001). In other words, maternal interaction style makes a considerable difference in children’s language development, perhaps because mothers who are less responsive are more likely to be more directive with their children and tend to engage children in fewer linguistic activities (Yoder & Warren, 1998). Maternal responsiveness and language outcomes are also strongly related in studies with clinical samples (e.g., late talkers, Hudson et al., 2015). Late- talking toddlers who had highly responsive mothers had higher language scores at 3 and 4 years, as compared to toddlers with less responsive mothers. One of the most important behaviors to consider when examining maternal responsiveness is mutual gaze. It is essential to consider mutual gaze in relation to maternal responsiveness because eye gaze help mothers in the interpretation of their children’s intentions (Golinkoff, 1986; Gros-Louis, West & King, 2014), which is crucial when responding to children’s needs. Also, mothers have reported feeling mutual love with their infant when their 2 infants started to have eye contact with them, referred to as mutual gaze, which might have been linked to a feeling of “being recognized” (Robson, 1967). It has long been known that mutual gaze is among the earliest markers of responsive parenting during infancy, and face-to-face interactions constitute a common characteristic of the early mother-child relationship (Schaffer, 1984, Stern, 1977; Trevarthen, 1974). Mutual gaze is a means of sharing positive affect (Feldman, 2007), and is not only a sign of responsiveness to a child, but also serves as a regulator of children’s emotions in situations of distress (MacLean et al., 2014). Similarly, maternal sensitivity, which is an important component of a responsive parenting, has been found to significantly relate to mutual gaze (Lohaus, Keller & Voelker, 2001). Maternal sensitivity refers to the quality of mothers’ responsiveness to their infants’ cues matching their developmental level and the demand of the context (Leekers, Blankson, & O’Brien, 2009). So, the emotional context of maternal responsiveness is important, and, in this sense, mutual gaze plays the role of providing strong positive feelings, which is important sign of emotional reciprocity between a child and their mother. Mutual gaze is considered to be a reliable way of creating a communicative connection between humans (Rogers, 2013; Farroni, Csibra, Simion, & Johnson, 2002), especially if it is done in a manner whereby mothers respond to children in an appropriate and well-timed manner (DiCarlo, Baumgartner, & Onwujuba, 2014, p.197). Children benefit from using their mothers’ face and eyes as a means to communicate shortly after birth (Hart, 2008). Mutual gaze is a particularly useful tool when examining joint attention, which plays an important role in the process of learning and memory from the early days of life through adulthood (Kim & Mundy, 2012). For joint attention to occur, a caregiver and a child display a mutual interest in an object or event (Akhtar & Gernsbacher, 2007; Tomasello, 1995). Focus of 3 attention can happen in the context of mutual gaze, gaze following, pointing, and social referencing. That is, gazing is a fundamental part of shared attention, and it is commonly stated that, “responding to or leading someone’s gaze to a location or an object of interest results in a situation of joint attention” (Staudte & Pfeiffer, n.d). Building on these visual aspects of joint attention, it is important to differentiate dyadic and triadic interactions when talking about joint attention. In fact, dyadic interactions involve two people sharing a mutual focus, for example when a mother and child have mutual gaze. On the other hand, triadic interaction is a skill that emerges by the middle of the first year, and it happens when an infant shares attention to another object and event with another person (De Schuymer et al., 2011 citing: Carpenter, Nagell, & Tomasello, 1998; Mundy, Sullivan, & Mastergeorge, 2009; Striano & Bertin, 2005; Striano, Stahl, & Cleveland, 2009). Similarly, researchers who are interested in when children start to be able to show joint attention skills found that the degree to which 6-month-olds engaged in joint attention predicted their vocabulary skills at 12, 18, 21, and 24 months of age (Morales, Mundy, & Rojas, 1998). Mutual gaze supports children’s ability to learn language (Akhtar & Gernsbacher, 2008). In particular, if we place mutual gaze in the context of joint attention and synchrony (i.e., both caregivers and children’s responsiveness to each other and their capacity to match their behaviors), mutual gaze can be seen as a means of sharing attention in the action of looking (Searle, 2001), and it creates a communication situation whereby joint attention can be initiated (Farroni et al., 2002). That is, mutual gaze creates the one-on-one interactions in which adults can talk directly to children, and this child-directed speech, not overheard speech, predicts child language (Weisleder & Fernald, 2013; Shneidman et al., 2013). 4 ARGUMENT FOR STUDYING MUTUAL GAZE AND CHILD LANGUAGE IN SENEGAL The importance of maternal responsiveness, and mutual gaze specifically, are well documented in Western settings, particularly in the USA, but non-Western cultures can have different parenting styles and may have different child-rearing objectives. This gap in the literature is confirmed by Arnett (2008), who analyzed 6 leading journals from the American Psychological Association and found that publications focused too much on American populations, who represent fewer than 5% of the world’s population. More importantly, less than 1% of the samples are from Africa. This means that the predominant body of research in our field does not give voice to the development of African children living in traditional and low- income communities. In addition, very little is known in terms of empirical studies investigating mother-child mutual gaze in Africa and its relations to children’s language outcomes. Given that human beings are defined in terms of their cultural participation (Rogoff, 2003), some parenting practices like mutual gaze may not be a universally relevant perhaps due to beliefs and childrearing objectives. For this reason, a goal of the present study is to reduce the gap in the literature with studies mostly conducted in the Western Educated Industrialized Rich and Democratic societies (Henrich, Heine, & Norenzayan, 2010), by providing a description of the nature, frequency, and duration of mutual gaze between rural Senegalese mothers and their children. Mutual gaze is a form of interaction reported in many studies to be associated with cultural norms in certain African societies. Some studies also showed that even though mothers from some non-Western societies engage in eye contact toward positive signals of their infants, it is something that they might not emphasize in their interactions with children (Keller, 2003). That is, these mothers would prioritize other parenting behaviors like physical contact, which 5 seems to minimize mutual gaze (Bard et al., 2005). Kâğitçibaşi (2007) reminds us that skin-to- skin parenting style (e.g., body contact system) is part of the four basic interactional systems in infancy along with the system of primary care (mainly nursing), the body motor stimulation system, and the face-to-face interaction system. However, there are cultural variations concerning the use of these systems when parenting infants. By way of illustration, researchers have found that body stimulation and skin-to-skin contact are more common in collectivist cultures such as agrarian African societies, whereas the face-to-face interaction system, including mutual gaze, is more prevalent in Western middle-class contexts (Kâğitçibaşi, 2007; Keller, Lohaus, Völker, Cappenberg, & Chasiotis, 1999). In West Africa, there are striking findings about cultural beliefs around mother-child mutual gaze. Mothers from some Kenyan ethnic groups deliberately avoid eye contact with their babies (Levine & Levine, 2016). Similarly, there are cultural beliefs noted in some Nigerian ethnic groups that ban mother-child eye contact during breastfeeding. In some Senegalese communities, mothers avoid having eye contact with their babies because of a belief in “evil eye” and fear of mystical dangers (Zeitlin, 2011). Thus, it is possible that mutual gaze would be infrequently observed during mother-child interactions in some parts of Africa. Some cross-cultural studies found differences between Africa and Euro-American mothers in terms of mutual gaze with their children. One comparative study between German middle class parents and rural Cameroonian parents showed that mother-child eye contact was more present in the German setting compared to the Cameroonian one, as mothers there focused more on body contact with their children as a dominant parenting practice (Keller et al. 2011; Keller, 2005). These mothers explained the importance of such patterns of parenting according to their culture. A German middle-class mother said, “Eye contact is absolutely important, that the 6 baby looks at the mother and seeks contact through the eyes.” Another German mother believed that “... communication in the first time is only possible through the eyes...” As for the mothers from Cameroon, they valued body contact and considered it good for helping the child to achieve optimal development (Keller et al. 2011, Keller, 2005). Likewise, when mothers from a subculture in Kenya were compared to American mothers, consistent differences were found among African and American mothers in terms of looking at their infants (Richman, Miller, & LeVine, 1992). When measuring gaze frequency, these researchers found that American mothers looked at their babies over three times more often (20%) than infants gazed at them (8%). But the frequency with which Kenyan mothers looked at their infants (9%) was almost the same as the frequency with which infants looked at them Despite the culturally bound behaviors reported by some studies in Africa about the lack of mutual gaze in parent-child interactions (Zeitlin, 2011), these observations are not necessarily generaliable to the Senegalese context. It is unknown whether mutual gaze is an important aspect of parenting in Senegal and how this aspect of parenting might relate to child outcomes. In fact, some anthropologists did observe mutual gaze in some traditional West African societies where babies were exposed to face-to-face interactions along with smiling and eye contact (Gottlieb, 2014). More importantly, we believe that mutual gaze is important for Senegalese children to acquire the Wolof language, as studies about the gaze coordination between children and adults showed that visual joint attention helps to avoid misunderstanding in communication, with high levels of joint attention making language learning easier (Schneider & Pea, 2013). Thus, mutual gaze should also constitute a basis for the development of communicative competence in Senegal as well (Lieberman, 2012). 7 Indeed, very little is known about mother-child interactions in Senegal. Senegal is a low- income country with a population of nearly 15 million people. More than 50% of the population lives in rural areas. It is a country with a low literacy rate, with only 37.5% of adults who can read and write, with rural areas being predominantly illiterate (Senegal National Census, 2013), perhaps coinciding with the high rate of poverty (i.e., 57.1%, Emergency Program for Community Development, 2012). Moreover, in the villages of Senegal, men are considered as heads of the households where women are particularly in charge of household activities, such as taking care of children, cooking, and getting well water. (Perry, 2015). Wolof is one of six codified national languages in Senegal (Senegalese Constitution, 2001), and the most widely spoken in the country. An extensive search for studies about child development in Senegal yielded only two articles. The first one is by Rabain-Jamin (2001) who observed the conversational activities of 21-27 months old Wolof children and the extent to which adults and older siblings support them. She found that polyadic types of communication in which children communicate with a broad network of adults mark the setting of Wolof families in Senegal. The second study was an intervention designed to reinforce parenting practices that would encourage rural mothers to talk more to their babies (Weber, Fernald, & Diop, 2017). This study reported on the evaluation of a parenting program called Stanford Tostan Evaluation Project (STEP), implemented by Tostan, a Senegalese NGO, in 24 Wolof-speaking villages in which nearly 500 families participated. The findings of the intervention showed that, from baseline to follow-up, mothers who participated in the program doubled the amount of talk they addressed to their children, in contrast to mothers in the matched comparison group, who did not increase the amount of child directed speech over time. Also, children from treatment villages showed greater language skills over time than did children from control groups. 8 In addition, the current study builds on the very limited previous research work on responsive parenting in Senegal. Since 2013, there has been a growing effort to enhance the parenting practices of rural Senegalese mothers (Tostan, n.d). One study in rural Senegal found that mothers who talked to their babies more had children with higher language skills (Weber et al., 2017). In order to encourage mothers and rural communities in rural Senegal to create an environment for children’s development, the NGO Tostan used simple techniques that enhance mother-child interactions. Some of those techniques were to encourage mother to look their newborn babies in the eye, follow the child’s lead during play, and describe objects to them. So, the current study aims at providing a comprehensive description of how often mothers have eye contact with children interact with their children in rural Senegal, including observations of mutual gaze between mothers and their children. We will also see if mutual gaze is associated with child language skills. 9 RESEARCH AIMS AND HYPOTHESES The study has two aims: 1. The first aim is to investigate the frequency, nature, and duration of mutual gaze between rural Senegalese mothers and their children as well mothers’ responsiveness to children’s attempt to have mutual gaze. We predict that most Senegalese mothers will use mutual gaze when interacting with their children. Regarding the nature, we hypothesize that the mutual gaze episodes will be dominated by positive emotions, and mothers will be the major initiators of the mutual gaze episodes. We also expect that mothers will most of the time look back when children want to establish eye contact with them. 2. The second aim is to explore relations between mutual gaze measures and child language outcomes. We hypothesize that mothers who have more or longer mutual gaze episodes with their children have children with higher vocabulary and language comprehension and production skills. 10 Participants METHODS Sixty Wolof speaking caregiver-children pairs from 17 villages in Senegal in the region of Kaolack participated in the study. Children’s age was between 20 and 30 months (M = 24.32, SD = 2.8), and there were 21 girls and 39 boys. The age range for caregivers was 16-67 years old (M = 30.33, SD = 10.59), and 75% of mothers had education levels that did not exceed elementary school. The dyads come from a larger sample (n=443) of an intervention program in Senegal (Weber, Fernald & Diop, 2017) designed to change parenting practices of rural Senegalese parents by encouraging them to engage in more verbal and nonverbal interactions such as talking and having eye contact with their babies. However, it is important to note that these data were collected at baseline, so these interactions took place before these families participated in the intervention. Measures and procedures Measures of gaze and procedure Using ELAN software, we coded mother-infant interaction in two tiers: Mutual Gaze and Child Gaze. Mutual Gaze. To capture the occurrences of mutual gaze, the 60 enrolled caregivers and their children were video-recorded for 15 minutes. A research assistant instructed the primary caregivers to play with their children as they did at home. The play settings were culturally appropriate and looked the same in all villages. Caregivers sat on a plastic mat and the set of standard toys that were on the mat for the play sessions were familiar to children and their caregivers. The middle 5 min were coded because we considered the first 5 min as being a warm- up time for caregivers and children being filmed maybe for the first time. 11 We were interested in the duration and frequencies of mutual gaze. Coders marked the entire duration of mutual gaze based on when both mother and child’s gaze aligned, until one or both discontinued the mutual gaze. The total duration was measured by calculating a sum of all mutual gaze instances across the whole 5-minute sessions. Within mutual gaze occurrences, we also measured two subcomponents, which were: Leader and Emotional context. Leader. We considered as leader whoever between child and mother first looked at the other in the eyes. It was basically who started or initiated the eye contact, which then led to mutual gaze (Mom =1, Child =2). Emotional context. We captured emotional behaviors that occured during mutual gaze: positive (code = 1), negative (code =2), and neutral (code= 3). Positive means that the mother and the child are showing signs of happiness when mutual gaze occurs (e.g., smile, laugh, joyful facial expression, caressing, touching etc. We coded mutual gaze instances as negative when signs of positive emotions, such as smiling and laughing, were not present. For example, mothers might look frustrated or be visibly upset. Neutral. We considered the interaction to be neutral when the socio-emotional ambiance of the mutual gaze was neither positive nor negative. Child Gaze. During the whole 5-min window, coders coded the duration of each individual gaze towards the mother’s face/eyes or at any time mutual gaze might happen. Twenty percent (20%) of the 60 videos were recorded for a reliability check. Prior to that, an undergraduate student was trained through multiple sessions during which she had six hours of coding practices. The inter-rater reliability on child gaze and mutual gaze yielded an overall 12 agreement of 85.5%. For the codes leader and emotional context, the agreement range was respectively 86% to 100%, and 83% to 100%. Measures of child language outcomes The MacArthur-Bates Communicative Development Inventories are report instruments that gather considerable information about many aspects of children’s early language abilities, including vocabulary comprehension, production, gesture use, and early grammar (CDI advisory board website, 2016). In this study, researchers from Stanford University had approval from the CDI advisory board in order to translate the short version of the CDI into Wolof. The adapted Wolof CDI checklist was initially 120-130 words but was reduced to comprise a short item form containing 105 words. This reduction was made after the piloting of the first form. The pilot version was obtained through an involvement of Wolof language specialists who also worked as research assistants in the study. Other existing versions of the CDI for West African languages (i.e., Krobo, Ewe, and Twi spoken in Ghana and in Malawi), were consulted for the development of the Wolof CDI (Weber, Marchman, Fernald, & Diop, 2018; Prado, 2011). The Wolof CDI used in this study had strong internal consistency with alpha >.86. (Weber et al., 2018). Validity was also measured using a sample of 500 children. The results showed a high correlation between vocabulary and milestones achieved in older children (rho= .79, p <. 001 (Weber et al., 2018). A considerable amount of time was allowed for the verification of the cultural, linguistic and developmental appropriateness with the support of Wolof native speakers, and the Wolof rural communities involved in the adaptation. Furthermore, in this study, a separate correlational analysis with the same participants confirm the CDI as a strong parent report for measuring language of Wolof children. 13 The 105-item form was used to measure children’s expressive vocabulary. The caregivers were asked to respond yes or no if they heard their child say the list of words read by the interviewer. The interviewers used probing skills in order to make sure that the caregiver understood the questions. For example, if the caregiver said that she heard her child say the word “animal”, the interviewer asked in what context she heard the child say that. Interviewers did not pay attention to the way the infant pronounced a word. For example, instead of saying “ndox” which means water, the child might say “ndo” to communicate this concept. In these cases, the child would still get credit for the word water. Language milestones. An adaptation of developmental milestones checklist has been done in Sub-Saharan Africa using the DCM-II for measuring motor, language, and personal-social development (Prado et al., 2014). Here we used a language milestones measure that was also adopted according to the linguistic and cultural context of rural Senegal. Data from 500 children showed strong psychometric results, Cronbach’s alpha = 0.86 & person separation = .88 (Weber et al., 2018). The relations between milestones and spontaneous speech obtained from video-recorded mother- child interactions showed that these measures are significantly correlated (rho=. 27). As with the CDI, a pilot version was created with the help of local child development experts as well as Wolof language specialists. The pilot test helped determine that the order of words, which were presented in order of difficulty, needed to be modified because some words are more challenging for American children when compared to Wolof children and vice versa. The caregivers were asked to report if their infant showed the behavior listed in the 36 items. For example, “Does your child babble?” (Put together similar sounds like dada...mama 14 etc.). The interview was stopped if the mother responded “no” for 6 successive items. The non- responded items at this level were scored “0”. 15 RESULTS Descriptive results 1. Mutual gaze frequency The results of the descriptive statistics for mutual frequency revealed that out of the 60 mothers enrolled in the study, 7 did not have eye contact at all with their children during a 5-min segment of interaction. However, overall mothers looked their children in the eye over 13 times in a 5-min interaction (SD = 11.83, M = 13.55, Median = 10.5), with a range of mutual gaze frequency that went from 0 to 53. Figure 1 shows the frequency distribution of mutual gaze instances between mothers and their children. 2. Gaze duration We calculated the total duration of mutual gaze for each of the 60 dyads. The results of the descriptive statistical analysis showed that rural Senegalese mothers had mutual gaze episodes that lasted, on average, over 25 sec in a 5-min segment of interactions (, M = 25.65, SD = 29.65, Median = 16.11). The total duration ranged from 0 to 119 sec. Figure 2 shows the distribution of the total mutual gaze duration. 3. Nature of mutual gaze The emotional context of mutual gaze in which mothers engaged with their children was predominantly positive with a mean score of 11.03, SD = 11. 282 as compared to negative and neutral emotions with scores of 0.6 (SD =1.39) and 2.07 (SD =3.23) respectively. For mutual gaze initiation, we found that random eye contacts were very rare (0.66 times on average, SD = 1.169), and mothers initiated mutual gaze (M = 8.87, SD = 7.637) more than children (M = 3.80, SD = 4.282). 16 Figures 3 and 4 show a graphic representation of the emotional context during mutual gaze episodes, and the average scores of mutual gaze initiation. 4. Mothers’responsiveness when children initiate mutual gaze Mothers looked back 34.47% of the time when children sought mutual gaze. This finding did not confirm our hypothesis that mothers would look back most of the time when children wanted to establish eye contact with them. Relations between mother-child mutual gaze and child language 1. Correlations The results of the correlations between mutual gaze measures are presented in Table 1. Based on the strong, positive correlation between mutual gaze frequency and mutual gaze total duration (r =.880**, p <.001) we chose to use mutual gaze frequency as our predictor variable. The choice of mutual gaze frequency as predictor is justified by this strong correlation, which means choosing either one would not make a big difference. In addition, both mutual gaze (r =.320, p <.05), and vocabulary (r =.463, p <.001) were positively and significantly associated with child age. 2. Regression analyses Summaries of the regression analyses are presented in table 2 and 3. A simple linear regression analysis was conducted to determine if children’s vocabulary scores from the CDI maternal report could be predicted by the number of mutual episodes that mothers had with their children. The results of the analysis showed that mutual gaze is a good predictor of children’s vocabulary. F (1, 59) = 4.911, p < .05. The CDI scores of rural Wolof children are expected to increase by .279 when the mutual gaze frequency with their caregivers 17 increases by 1. These results confirmed our hypothesis that mother-child mutual gaze is significantly associated with children’s language outcomes through their vocabulary size. However, we did not find a significant association between measures of mutual gaze and language milestones for Wolof children, which test language comprehension and production, F (1, 59) = 2.285, p = .136. Tables 2 and 3 respectively present the summary of regression analyses for CDI and Language Milestones. 18 DISCUSSION The goal of the study was to describe the frequency, nature, and duration of mutual gaze between Wolof speaking mothers and their children in rural Senegal during face-to-face interactions, and also to look at the relations between mutual gaze and children’s language skills. The study yielded three main findings. First, in a 5-min window of face-to-face interactions, Wolof mothers and their children looked each other in the eye on average 13 times, with a mean total mutual gaze duration of over 25 sec. Second, we found that mother-child mutual gaze happened very rarely in a context of negative emotions (e.g., threatening the child not to do something), as mothers were observed to exhibit predominantly positive emotions (e.g., smiling, laughing, singing) when having eye contact with their children. Wolof mothers also initiated mutual gaze more often than children. Coincidental eye contact, coded as when mothers and children simultaneously look at each other in the eye, was found to be very rare. Third, mutual gaze frequency was significantly and positively related to Wolof children’s vocabulary. Explanation of the findings Our study suggests that Senegalese rural mothers look their children in the eye often; instances of mutual gaze may even be more prevalent than those observed for Western mothers in other work. For example, a study conducted by Farran and Kasari (1990) found that American mothers and their 20-month-old children on average looked each other in the eye 23.4 times, and an average mutual gaze duration of 47.0 seconds based on 20-minute interaction sessions. These sessions are 4 times longer than the interactions in this study, which were 5 minutes long during which Senegalese mothers have mutual gaze with their children 13.55 times with an average duration of 25.65 seconds. So, if participants had interactions of the same length, their mutual gaze frequency and duration could be more than what Farran and Kasari (1990) found. That is, 19 mothers in Senegal use an important number of mutual gaze instances, suggesting that it is a core part of mother-child interactions there. Mutual gaze has been proposed to be useful because it creates good communicative connection (Rogers, 2013) between mothers and children, and this does not appear to be something that is unique to Western countries. The findings about the nature of the mutual gaze instances between mothers and children contrast with prior work indicating that mutual gaze is deliberately avoided in African communities for cultural and mystical reasons (LeVine, & LeVine 2016; Zeitlin, 2011). It is possible that Senegalese mothers, unlike some mothers in certain African subcultures, who avert their eyes when their children get overtly exited (Richman, Miller, & LeVine, 1992), do not have cultural restrictions to look at their children in the eye. In fact, this link between mother-child eye contact and social norms has been widely reported in previous studies conducted in Africa (Levine et al., 1994). Some of them report that due to those cultural restrictions, mothers from a subculture in Nigeria report only looking at their children in private in order to avoid the stigma that would result from the judgment of others (LeVine & LeVine, 2016). The reason why Senegalese mothers could potentially have more eye contact with their children than shown in prior work by Farran and Kasari (1990) may be due to the age difference between children. The children in our study ranged in age from 20 to 30 months, whereas prior work the children were all only 20 months of age. In our work, mutual gaze was positively and significantly related to age in the current work, such that mothers and children engaged in more eye contact with older children. Thus, older children may engage in more social communications that involve eye contact. This point is confirmed in previous studies where age is positively related to the amount of gaze initiation by mothers and children (Farran et al., 1980). 20 Wolof Senegalese mothers living in rural Senegal also exhibit positive emotions when displaying eye contact with their children. The caregivers’ enjoyment during the interaction is noted through a high rate of positive emotions expressed through smiling, tone of voice, and facial expressions. In addition to the generally positive nature of these mother-child interactions, it was observed that parents not only initiated mutual gaze twice as often as children, but also spent a significant amount of time being responsive to children’s search for eye contact. This finding shows variations in terms of mutual gaze interactions in Africa; because former studies done with a subculture in Nigeria found that mothers were relatively unresponsive to their infants’ attempts at eye contact and only 1% of them engaged in interactions that included looking at children (Richman et al., 1992). It appears that rural Senegalese mothers are more responsive to eye contact than the Nigerian mothers observed in prior work, as mothers were responsive more than 34% of the time when their children attempted to make eye contact. In addition, our results indicating mothers are major initiators of mutual gaze is consistent with what was found in previous studies conducted in Western societies where mothers most often initiated mutual gaze (Farran et al., 1980). Senegalese mothers’ higher rate of mutual gaze initiation can also be interpreted in the context of social interactions in which children interact with adults or simply “more knowledgeable others” (Vygotsky, 1978) who naturally lead verbal and non-verbal interactions that put children in a nurturing learning situations. A major finding from the study is that mothers who had more eye contact with their children had children with better language skills. In fact, there are processes through which children language skills might depend on aspects of mutual gaze. First of all, we can understand the relation between mother-child mutual gaze and Wolof children’s vocabulary skills by placing mutual gaze in the context of dyadic synchrony. In the context of mother-child relationships, 21 synchrony includes both the child and the mother’s responsivity to each other (Leclère et al., 2014), and mutual gaze frequently sustains this synchrony because it allows children and caregivers to maintain engagement during the interaction and to visually “track” each other (Beebe, Stern, & Jaffer, 1979). This dyadic synchrony has been found to support children’s language skills in other work (Landry et al., 2001). For example, mothers can help children to map words to their referents that in turn supports children’s vocabulary growth (Tamis- LeMonda, Kuchirko, & Song, 2014). Further, the Wolof children in this study are toddlers, and one of the functions of synchrony in toddler-caregiver interactions is to facilitate communication skills and language acquisition (Harrist & Waugh, 2002). This includes learning word-object relations, and the naming of object wholes (See Leclère et al., 2014 for a literature review). Mutual gaze can create optimal conditions for language learning. For example, besides maintaining the coordination of interactions between a child and a mother, it also indicates attention when the other person is speaking (Rutter & Durkin, 1987). In addition, our results confirm findings from previous studies since mutual gaze activates the semantic knowledge system of children by helping them learn about new objects, mutual gaze is also a learning experience for children and a way of enhancing their vocabulary knowledge as it is reported in other studies (Hoehl, Michel, Reid, Parise, & Striano, 2014). The relation between mutual gaze and language skill makes sense because children selectively pay more attention to speakers, who look at them directly while speaking (Marno et al., 2006), and they use the eye gaze of their caregiver during interaction as “source of information to guide their attention” (Niedzwiecka, Ramotowska, & Tomalski, 2017). In addition, it is also possible that children with better language skills elicit more mutual gaze from mothers. In the second and third year of life, most children rapidly learn their native 22 language (Bates & Goodman, 2001), although proficiency varies greatly across children. It is possible that those children who have stronger language skills might do a better job in having their mothers’ attention and maintaining sustained interactions with them, which in turn can provide more opportunities for mutual gaze. We found that the CDI and the number of words expressed by children during the 5-minute interaction with their caregivers have a high and significant correlation (r = .503, p < .001). This finding is consistent with previous studies conducted in Western societies where a positive and significant association was found between CDI and children’s spontaneous expressive language (Pan, Row, Spier, & Tamis-Lemonda, 2004). The current study builds upon prior observational and anthropological works in Africa. These studies were just conducted in some parts of West and East Africa. For these reasons, they may miss important variations about mother-child mutual gaze that exist in the African continent with encompasses more than 2000 languages and thousands of ethnic groups (Obadina, 2014). It also gives a comprehensive picture of the ways in which African caregivers engage their children in mutual eye gaze, which is a distal parenting strategy that has been so far reported in cross-cultural research to be more frequent in Euro-American societies than in African societies where proximal parenting strategies, including body contact, are favored (Keller, Yovski et al., 2004). To our knowledge, the present study is the first to not only provide quantitative analyses of mutual gaze and children’s language skills in Senegal but also to show that face-to-face interaction in general as a parenting system, and mutual gaze in particular, is important for Senegalese children’s learning. Mothers showed positive affect and frequently made eye contact with their children. So, when integrated with previous work, this study calls on the cautiousness 23 of child developmental researchers to not generalize the idea that certain nurturing parenting practices due to social norms, are avoided in Africa as a whole. Implications of the study and directions for future research As the first study to investigate mother-child mutual gaze in Senegal, results suggest that mother-child eye contact is related to the language development of Senegalese children. There are, however, many avenues for future research in this area. Qualitative methods could provide a more nuanced understanding of the grounded cultural and behavioral aspects of mutual gaze in rural Senegal. More specifically, the qualitative method would include focus groups and individual interviews asking about the beliefs of caregivers in having eye contact with their children. It would also include direct observations focused on the face-to-face interactions between children and adults. This would help us understand the behaviors of the Wolof mothers who did not look their children in the eye and if the reason why others had less frequent and very short eye contact, is due to social norms as reported in previous studies mainly in Nigeria, and in Kenya (LeVine & LeVine, 2016). Limitations Our study is limited by the fact that we did not observe caregivers and children in their natural environments. Although the play sessions were devised to emulate real-world settings in Senegal, it is possible that other aspects of parenting would be revealed if the day-to-day interactions of mother and children were videorecorded in their home environments. Since communities’ ways of interacting with others are culturally and ecologically grounded in their everyday life (Keller & Kärtner, 2013), observing the caregivers and children in their real-word environment could give a fairer picture of their face-to-face interactions. It is possible that rural Senegalese participants were affected by the unfamiliar lab-designed room and possibly 24 unfamiliar technology. A direct observation of participants in their home environment could give us an accurate picture of the culturally grounded face-to-face interactions that Wolof families engage in with their children. Another limitation is the fact that we did not include factors that might affect mothers’ gaze. For example, a key factor to consider would be maternal depression since depressed mothers showed less emotional availability during mother-child interactions (Kluczniok et al., 2016), so it might be something to consider in this study as well. A few mothers in our study did not engage in any mutual gaze with their children at all, which could perhaps be explained by factors such as depression. 25 CONCLUSION The current study extends our understanding of how African mothers and their children interact, by providing us with a thorough description of the frequency, duration as well as the nature of mutual eye gaze interactions of rural Senegalese mother-child dyads. Results show that mutual gaze is a frequent practice in rural communities of Senegal. This type of description adds useful characteristics of mother-child mutual interactions in Africa, by providing the emotional context, mutual gaze initiation and maternal responsiveness to children’s bids for mutual gaze. Those components of mutual gaze were missing from previous studies conducted in Africa since many of them were mainly culturally oriented. In addition, the study goes beyond description, and shows that mutual gaze is strongly related to children’s language skills, which suggests that as in Western societies, mutual gaze is also important in the language leaning of African children. 26 APPENDICES 27 Appendix 1: Tables Table 1: Correlations between Mutual Gaze Measures Mutual Gaze Measures 1 1. Mutual Gaze Total Duration -- 2. Mutual Gaze Mean Duration 3. Mutual Gaze Frequency 2 .749** -- 3 .880** .553* -- Table 2: Summary of linear regression with CDI scores as the outcome (N = 60) Model B(SE) β B t Mutual Gaze .712 .321 .279 2.216 Frequency Sig. .031 Table 3: Summary linear regression with Language Milestones scores as the outcome (N = 60) B B(SE) β t Model Sig. Mutual Gaze Frequency .088 .058 .195 1.511 .136 28 Appendix 2: Figures Figure 1: Frequency distribution of mutual gaze instances Figure 2: Distribution of total gaze duration 29 Emotional Context Within Mutual Gaze S E R O C S E G A R E V A 12 10 8 6 4 2 0 Positive Emotions Negative Emotions Neutral Figure 3: Emotional Context Mutual Gaze Initiation S E R O C S E G A R E V A 10 9 8 7 6 5 4 3 2 1 0 Mom Child Both Figure 4: Mutual gaze initiation 30 REFERENCES 31 REFERENCES Critical Look. Language and Linguistics Compass, 1(3), 195–207. African Holocaust. (n.d). African People. http://www.africanholocaust.net/peopleofafrica.htm Akhtar, N., & Gernsbacher, M. A. (2007). Joint Attention and Vocabulary Development: A Akhtar N, Gernsbacher MA. 2008 On privileging the role of gaze in infant social cognition. Baldwin, Dare A. Understanding the link between joint attention and language. In: Moore, Chris; Child Dev. Perspect. 2, 59–65. (doi:10.1111/j.1750-8606.2008. 00044.) 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