The influence of parental socio-communicative functioning on the
early emotional communication
Naam:
Maaike Gemmeken
Adres:
Nauerna 56
Woonplaats:
Zwanenburg
Telefoon:
0620198231
Studentnummer:
11130288
Emailadres:
maaikegemmeken@hotmail.com
Onderwerp:
Inter-Personal Synchrony of Emotional Communication
Ingeleverd:
24-05-2019
Toewijzing leerstoelgroep: OOP
Begeleider:
dr. Eliala A. Salvadori
Abstract
In the first months of life, infants get introduced to- and learn about the social world mostly through the interactions with their parents. During this interaction, they connect through a relationship that allows a bi-directional flow of information and reciprocal responses to verbal and nonverbal signals. This is described as interpersonal synchrony of emotional communication. Parent-infant synchrony lays the foundation for the infants’ later capacity of engaging in social interaction throughout life. Through parent-infant synchrony, socio-communicative functions, such as symbol use, empathy and self-regulation, mature in infants. This study investigated how parental socio-communicative functioning influences the level of parent-infant synchrony, in order to better define the role of parents in the development of social understanding in early infancy. Sixty-six family’s with an infant, 32 boys and 33 girls (M age= 4 months, 21 days), were observed during a two minute observation of a face-to-face interaction at home to measure the parent-infant (visual, affect and vocal) synchrony. Both parents’ socio-communicative functioning was self-reported with the ‘Autism-Quotient’ questionnaire. Correlation coefficients and one way analysis of variance show that mothers and fathers are equally capable of engaging in visual, affective and vocal synchrony with their infant, confirming previous research. A significant relation between Attention to detail of parents and Positive affect synchrony during parent-infant interactions was found. These results are the first signs of the suggested influence of parental socio-communicative functioning on parent-infant synchrony. Further research should include a more varied, larger sample and for comparison, a clinical population.
Keywords: parent-infant interaction, emotional communication, socio-communicative functioning, interpersonal synchrony
Table of contents 1. Introduction
1. Emotional communication
2. Inter-personal Synchrony of Emotional Communication 3. Parental socio-communicative functioning
4. Current study 2. Method 1. Participants 2. Measurements 3. Behavioral coding 4. Statistical Approach 3. Results 1. Descriptive statistics 2. Main analysis 4. Discussion 5. Literature 6. Appendix
Introduction
Early parent-infant interactions play a central role in children’s later development; as they are critical for learning, later psychological development and psychopathology (Cohen, 2012). During these interactions, parent and infant connect through a bi-directional flow of emotional communication and reciprocal responses to verbal and nonverbal signals. Individual differences in the capacity to contribute to the interactions from each member influences the quality of these relationships of information exchange. One factor that affects the quality of these interactions is the responsiveness of the parent to the infant’s social signals. Important is that the parent is able to perceive the infants’ signals on time and accurately (Lohaus, Keller, Ball, Elben & Voelker, 2001). Another important factor is the sensitivity of the parent, namely an appropriate respond to these social signals of the infant. Early observations of the interactions between parent and infant showed that the dyad is a complex system in which each member influences and is influenced by others (Tronick, Als, Adamson, Wise & Brazelton, 1978). In order for the infant and parent to communicate with each other, they must be connected through a relationship that allows for a reciprocal flow of information and emotions, for processing and responding to verbal and nonverbal signals. Very young children communicate to their interaction partners by using their emotional communication. Emotional
communication is described as the modulation of emotional states (Schore, 2001, 2003), such as social gaze to express their attention and interest, and numerous facial expressions, vocalizations, changes in postural tone and body positioning to express their internal emotional states. Infants’ use emotional communication to both respond to the parental communicative cures, and to initiate conversations with their parents. At 4 months old, the infants’ skills to regulate their internal emotional states has matured and the ability to communicate through their emotions and engage in social interactions has
developed. This means that from 4 months old on, dyadic interaction is possible (Beebe et al., 2016; Stern, 1985; Tronick, 1989).
Interpersonal synchrony of Emotional communication
The early emotional communications are the first signs of affiliation and social attitude to familiar and unfamiliar social partners (Lin & Green, 2009). There are three main expressive modalities of emotional communication, namely, the visual, the affective and the vocal (Lavelli & Fogel, 2005; Messinger & Fogel, 2007; Yale, Messinger, Cobo-Lewis & Delgade, 2003). The visual modality is the direction of gaze and can be seen as a measure of the social interest and direction of attention of the infant (Weinberg & Tronick, 1994), whether on the interaction partner or somewhere else. The affective modality consists of the expressions of the affective states of the infant and include a broad repertoire that ranges from positive to negative emotions (Messinger, 2002). Positive emotions are shown by producing open or closed smiles and negative emotions are shown by sad expressions and frowns (Ekman & Friesen, 1978). Infants also attempt to communicate and obtain attention by vocalizations (Jaffe, Beebe, Feldstein, Crown & Jasnow, 2001). During dyadic face-to-face
interactions infants coordinate these modalities in different ways. This has been often studied in terms of intrapersonal synchrony, by timing the temporal overlap (i.e. co-occurrence) of the communicative behaviors during social interactions with the parents (Yale et al., 2003). The results showed that infants usually produce smiles while producing a vocalization while also gazing in the direction of the parent for approximately 80% of the time (Colonessi et al, 2012). During these parent-infant
interactions, infants gaze to their parents most of the time (Colonnesi et al., 2012; Weinberg & Tronick, 1994; Yale et al, 2003). In addition, infants show more smiles than negative facial expressions and most smiles are coordinated by gazing at their parent (Crown, Feldstein, Jasnow, Beebe & Jaffe, 2002; Fullmer & Messinger, 1997; Messinger. Fogel & Dickson, 2001; Colonessi et al., 2012). The coordination of the expressive modalities of emotional communication during the first months of life may be important to later social communicative development (Colonnesi et al., 2012). Using and coordinating these expressive modalities in dyadic interactions may contribute to the development of skills for intentional communication (e.g., referential abilities), starting at the age of 8 months. Using the expressive modalities in combination with gestures will enable the infant to
communicate through their emotions about an experience of a specific object or event (Colonnesi et al., 2012; Colonnesi, Rieffe, Perucchini & Koops, 2008).
Due to the important and dynamic relationship between the infant and their parents, the flow of the exchange of emotional communication during parent-infant interaction has been investigated (Weissman, Zagoory-Sharon & Feldman, 2012; Weissman, Zagoory-Sharon, Schneiderman, Gordon & Feldman, 2013), leading to the studies of interpersonal synchrony (Feldman, 2007). In general, synchrony is described as a relation that exists when two or more events occur at the same time and cohere into a single process (Merriam-Webster Medical Dictionary, 2002). Synchrony in the context of human interactions addresses the reciprocal and dynamic pattern of temporal co-occurrence of verbal or non-verbal behaviors between social partners (Delaherche et al., 2012). Differently from mirroring, synchrony describes the ‘dance’ of communicative behaviors that arises during short and intense face-to-face interactions. From birth onwards, parents and their infants use these behaviors to communicate with each other (Hart, 2010) and it’s typically observed from the third month of life. At 3-6 months synchrony occurs in various modalities, like the visual, vocal, affective and touch, and is an ongoing match of micro-levels behaviors and affective states between parent and infant that together form a dyad (Feldman, 2007). Towards the end of the first year, synchrony occurs in parent-infant-object triadic coordination’s and the use of symbols in words and gestures of the infant (Feldman, 2007). It builds on the familiarity with the partners’ behaviors and interaction rhythms (Stern, 2002). Essential for parent-infant synchrony are temporal parameters of the interactive flow, the ongoing match of affective states, perceiving and mirroring of the infant’s communicative signals, and the parent’s transformation of the infant’s social desires into sensory modalities (Beebe &
Lachmann, 1988; Stern, 1974, 1999; Trevarthen, 1993). Thus, sensitive parenting is crucial for parent– infant synchrony (Lundy, 2002, Lundy, 2003; Weinberg, Tronick, Cohn & Olson, 1999).
Healthy developing parent-infant dyads do not achieve perfect synchrony at all times, but shift from moments of engagements to moments of disengagement and back again (Gianino &
Tronick,1988). Each interaction partner plays an important part in restoring synchrony during interactions; even infants have coping behavior for repairing mismatch during interactions (Tronick, Als & Brazelton, 1977). Parents and infants learn about themselves and each other and develop their capacities for self‐regulation, co‐regulation, and mutual regulation as they experience these brief mismatches and engage in trial and error efforts to make reparations and engage once again (Gianino & Tronick,1988). A considerable number of studies, mostly on mother-infant interaction, showed that the quality of mutual regulation in early face-to-face interactions effects the developing mother-infant relationship (Hsu & Fogel, 2003), with important consequences for 12 month attachment (Feldman, 2007), and later cognitive (Feldman & Greenbaum, 1997) and social-emotional development (Feldman, 2007). In addition, Leclère et al. (2014) made an overview of studies looking into
synchrony during early mother-infant interactions in a general population, and found that synchrony has an impact on cognitive processing, school adjustment (Harrist, Pettit, Dodge & Bates, 1994), learning of word-object relations (Matatyaho & Gogate, 2008), naming of object wholes more than object parts (Gogate, 2010) and IQ (Feldman, Greenbaum, Yirmiya & Mayes,1996; Feldman, 2007). Synchrony also predicts a better adaptation in empathy in adolescence (Feldman, 2007), symbolic play and internal state speech (Feldman & Greenbaum, 1997), relation between mind-mindedness and attachment security (Lundy, 2002, 2003). Additionally, the interaction may be poorer when maternal sensitivity and parental empathy is impaired (Feldman, 2007). To better understand the parent-infant dynamics and identify the synchronic patterns may be important for the detection of impairments in the interactions and provide early intervention (Guedeney, Guedeney, Wendland & Burtchen, 2014). The quality of social skills of normally developing children builds on the first parent-infant
interactions (Crown, Feldstein, Jasnow, Beebe & Jaffe, 2002). Therefore, synchrony can be described as the temporal co-occurrence of micro-social behaviors into patterns that become internalized and shape the social development of the infant over experience and time (Gordon & Feldman, 2008). Each interaction with the parents creates its own communicative patterns (Hsu & Fogel, 2003; Tronick, 2003) that will organize the infants’ later behavior and engagement with the world (Tronick & Beeghly, 2011). Infants of 2 months are more responsive to smiles and vocalizations of a stranger when the strangers’ responsiveness is more or less contingent than that of their mother, what could suggest that the interaction of infants with others is already based on their relationship with their mother (Bigelow & Rochat, 2006). Infants of 3 months with more attuned mothers, smile and gaze more at their mothers than infants with less attuned mothers (Legerstee & Varghese, 2001). These studies indicate that early miss-attunement from the mother biases the infant toward dysfunctional
patterns of communication (Beebe & Jaffe, 2008; Beebe & Lachman, 2002; Feldman, 2007; Field, Diego & Hernandez-Reif, 2009).
In these early social interactions, the parent’s gender seem to have an important role
(Colonnesi et al, 2012; Feldman, 2003; Forbes et al., 2004). Indeed, although infants coordinate their vocal communication, facial expressions and visual attention similarly with both parents, there is a longer positive emotional communication with their mother (Colonnesi et al., 2012). Specifically, infants produce more smiles and gaze longer to their mother during their interactions than with the father. Also, positive facial expressions are more often coordinated by infants with gaze and
vocalizations when interacting with their mothers. This could be interpreted by the fact that generally mothers spend more time with their infant in comparison to fathers (Colonnesi et al, 2012), especially in the first months of life of the infant. Thus, it may be argued that since mothers spend more time alone with the infant, they might have developed more game routines during their interactions, such as peek-a-boo games. This could result into a specific communication pattern, in which the infants’ communication is characterized by combinations of smiles with gazes and vocalizations to their mother. So, the interactive history with a lot of positive affect between mother and infant may influence the more positively oriented face-to-face communication. Because mothers are known to have more positive and social oriented communication, Colonessi et al. (2012) suspect that this
suggest that the higher number of smiles of infants in combination with gaze to their mother during the interaction could be a synchronic reaction to the mothers’ communication (Feldman, 2003).
Although most of the research has been done on the synchrony in mother-infant interactions, results from a study by Feldman (2003) showed that mothers and fathers are equally capable of engaging in interpersonal synchrony with their infant. The level of parent-infant synchrony was higher in same-gender dyads, because of a closer match between the partners’ emotional communication. This can be a result of gender differences in inborn arousal- and emotion regulation. Mothers vocalize more than the father does (Brundin, Rodholm, & Larsson, 1988), and girls seem to react better to the vocalizations of the mother than a boy does (Gunnar & Donahue, 1980). Also, faster responses from the mother to facial expressions of girls (Haviland, 1977), could shape the interaction as a social form of regulation, expressed in shared facial expressions, co-vocalization and shared gazing. Differently, fathers seem more often involved in physical play with the infant, like rough and tumble games, and show more ‘high intensity turns in positive arousal’ (Parke, 1990; Lamb and Lewis, 2004). In addition, the synchrony between boys and father shows to be more arousing, and this interaction with quick-peaks of joy may be a better fit for boys, because this interaction style is comparable to the boy’s internal expression of arousal. Because the interaction with the father is more physical rather than socially focused, it may suit the boy’s lower inborn interest in social contact better (Osofsky & O’Connell, 1977).
Socio-communicative functioning
Very little is known about the role of parental socio-emotional dispositions and how this influences the child-infant synchrony. Parent-infant interactions play a central role in children’s later development and social skills. Because of this important role of parents, this current study will investigate how parental socio-communicative functioning influences the parent-infant synchrony at four months old. To measure the social and communicative abilities of the parents, this study used the Autism Quotient Short Form, a questionnaire that measures the presence of a range of autistic traits in adults with an average intelligence in the normal population (Baron Cohen et al., 2001). It is
developed in accordance with the diagnostic criteria of the DSM IV-TR of the Autism spectrum disorder (ASD). ASD is a complex, neurodevelopmental disorder and is characterized by two main domains: impairments in social communication and social interaction and having of restricted interests, stereotyped behaviors and activities (American Psychiatric Association, 2013). The
impairments already appear in early childhood and are effecting the ability to successfully function in a social world. Genetic factors play an important role in vulnerability to an ASD (Losh, Sullivan, Trembath & Piven, 2008). Recent work suggests that the probability of a younger sibling receiving the diagnosis when an older sibling has ASD is almost 19% (Ozonoff et al., 2011). Though ASD is considered highly heterogeneous (Murray, Booth, McKenzie, Kuenssberg & O’Donnell, 2013), there is a difference in the degree of impairment in each of these characteristics. This is the reason the DSM-5 identified autism as a spectrum disorder. Those who score at the extreme end of this spectrum, which is a distribution of abilities and traits related to socio-communicative adaptation, will be diagnosed with an ASD (Constantino & Todd, 2005). In the general population, a distinction is made between clinical autism and autistic like traits (Murray, Booth, McKenzie, Kuenssberg & O’Donnell, 2013). The difference is that those with a clinical diagnosis of ASD have significantly impairment in social functioning, whereas those who have autistic like traits but without a clinical diagnosis of ASD remain better able to cope with the daily social interaction demands of society (Lundström et al, 2012). Constantino and Todd (2005) showed that children whose parents have autistic traits are more likely to show autistic traits themselves. A low level of autistic traits, not severe enough for a clinical diagnosis of autism, have been shown to be present in the family members of a person with ASD (Pickles et al, 2000; Piven et al, 1997), and such traits can point to a potential family genetic sensitivity to ASD. Crucially, parents seem to play a critical role in the development of social understanding of children. Low socio-communicative functioning of parents might be an early indicator of an infant’s genetic vulnerability for ASD (Constantino & Todd, 2005). Also, this parental low socio-communicative functioning can be reflected by a low level of synchrony during early emotional communication with the infant. There is a necessity to better define the role of parents in the development of social understanding in early infancy. Little is known about the role of social predispositions.
Current study
This current study is the first study investigating how parental socio-communicative
functioning influences 4 month old infants’ early emotional communication. Because parents play a critical role in children’s development of social understanding, low parental socio-communicative functioning might indicate the infants’ genetic vulnerability for ASD in the early months of life. To provide earlier interventions, based on strengthening the first socio-emotional communication, there is the necessity to anticipate the detection of autistic traits and socio-communicative problems in early infancy. The first hypothesis of this study is that traits for autism (low socio-communicative
functioning) in adults from the general population could be related to low levels of synchrony of gaze, vocalizations and facial expressions measured in a face-to-face interactional paradigm, with 4-month olds and their parents. First, to verify this, the parents were asked to complete the self-reported ‘Autism-Quotient’ (Baron-Cohen et al., 2001) to determine their level of socio-communicative functioning. Second, the relationship between the visual, affect, and vocal synchrony between the parent and infant and the level of social-communicative functioning of parents were studied by using micro coding of the emotional communication. Since both sub-clinical autistic traits and ASD are more prevalent in male than female subjects (Amaral, Schumann & Nordahl, 2008; Baron-Cohen et al, 2001, 2011; Constantino & Todd, 2003), the second hypothesis is that fathers, as compared to
mothers, show more autistic traits and thus lower synchronizing of gaze, vocalizations and facial expressions will occur paternal interaction than maternal interaction. Last, for hypothesis three, given findings of Feldman (2003) it was hypothesized that the level of synchrony among same-gender dyads would be higher, in terms of longer co-occurrences of behaviors between the interacting partners.
Method Participants
This research project is a part of the ongoing longitudinal study ‘My-BEST’, a study on infant’s emotional and social trajectories, in which infants and their parents were observed over a time span of 14 months. In the current study, the participants from ‘My-BEST’ and the 4 month
measurement have been used. Participants were sixty-six families with a 4 month old infant (within a range of 2 weeks), 32 boys and 33 girls, with an older sibling(s). In the participating families, the mothers’ average age was 34.21 years (SD= 3.03), and fathers average age was 37.41 years (SD= 4.09). The highest level of completed education for mothers was 8.7% secondary education or MBO, 35.3% HBO, 41.2% University, 11.8% specified their education as otherwise and 2.9% was missing. For fathers: 14.7% secondary education or MBO, 26.5% HBO, 41.2% University and 11.8% specified their education as otherwise. The current working situation at that time for mothers was 11.8% working fulltime, 47.1% working part-time and 58.9% was unemployed, housewife or sick leave. For fathers: 73.5% working fulltime, 20.6% working part-time and 5.9% was missing. Participants were all healthy, full-term infants with no pre- and postnatal medical histories. The participants were
recruited during pregnancy or just after birth, through brochures provided at pregnancy courses, kinder gardens, schools, childcare centers, child health centers and by midwives. Recruitment also took place through social media (e.g., Facebook groups for mothers). Parents were able to enter the study by filling in a short online screening questionnaire to examine whether the families met the inclusion criteria of the study, namely having a newborn baby with older sibling(s). Through the screening, information about the (expected) date of birth, gender (if known) of the newborn baby, the biological parents, the age of older sibling(s), and possible developmental problems of the older sibling was retrieved. The parents were given a compensation of 10,- euros as a gift, thanking the family for participating.
The current study has been approved by the ethical committee of the Research Institute Child Development and Education of the University of Amsterdam. Participants signed an informed consent for participating in the study. By doing so, it was possible for the parents to terminate enrolment in the study at all times.
Design and procedure
The data for the current study were collected by the researchers and students of
Orthopedagogy and the Research-master of the RICDE of the University of Amsterdam. The study consisted of two testing phases. First, parents received an email containing a link for the online Qualtrics survey to fill in: the socio-demographic questionnaire and the self-reported ‘Autism-Quotient’ (other questionnaires were administered but these were not of interest to the current study). The short socio-demographic questionnaire consisted of the parental information about country of birth, civil state, educational level and professional level. Both parents filled out the questionnaires individually. Secondly, two weeks later, two experimenters went to the participants’ homes, in order to create a semi-structured observation of the children and parents’ behavior in a familiar and natural setting, to observe the infant and parents’ spontaneous and typical behavior. A naturalistic observation would be more representative because of the real interaction dynamics. The ecological validity is higher at the family’s home than a laboratory setting but it could also result in a, less standardized observation. To control for distraction, during each home visit the same setting was used (see Figure 1) and before the observation started, the experimenters kindly asked if while a parent is interacting with the infant, the other parent could look after siblings in another room.
Infants and their parents were observed during dyadic face-to-face interactions. A face-to-face interaction is a common situation to measure both the behavior of parents and young infants, and observe the interaction and turn-taking at a micro-level (Feldman, 2003; Murray et a., 2007). By observing the face-to-face interaction of the parent and infant, it is possible to investigate these interactive patterns by measuring how they align and synchronize their verbal and non-verbal
communication (Hsu & Fogel, 2003; Lavelli & Fogel, 2013). Before starting the observations, parents were asked to sign an informed consent, standard with studies testing minors. The home visits took
approximately one hour in total and the observations of the dyadic interactions with the parents took two minutes each. The order of the interactions were counterbalanced within infants’ gender. During the observations, the experimenters would either hide in another room, or in case that this was not possible, they would sit on the other side of the room behind the baby. The infant was placed in a maxicosi on a table and the adult sat in a chair facing the infant, about 20 cm away. The camera was attached on a tripod, which stood in between the parent and the infant, as in Figure 1. The interactions were recorded by a 360 view Samsung camera, which provided a split screen with the face and upper body of both social partners. The parents were instructed to interact with the infant as they normally would, but without using any external toys, in order to elicit the dyads’ typical interactive patterns. Measures:
Parents’ Socio-communicative functioning Parents’ socio-communicative functioning was measured using the Dutch version of The Autism Quotient (AQ: Baron-Cohen, S., Hoekstra, R. A., Knickmeyer, R., & Wheelwright, S., 2006). This is a self-report questionnaire that tests the presence of a range of autistic traits in adults with average intelligence in the normal population (Baron Cohen et al., 2001) and is developed in accordance with the diagnostic criteria of the DSM IV-TR, which include impairment in social interaction and communication. The Dutch translation was created by Hoekstra, Bartels, Cath, & Boomsma (2008) and has satisfactory psychometric properties. The Dutch AQ consist of 50 items on a 4-point Likert scale (1 = ‘‘definitely agree’’ up to 4 = ‘‘definitely
disagree’’). All the scores on the items were summed up, resulting in a minimum total AQ score of 50 (no autistic traits) and a maximum score of 200 (full score on all items). The 5 subscales of the AQ are Social skills, Attention switching, Communication, Attention to details and Imagination (Baron-Cohen et al., 2001). In a study to the Dutch translation of the AQ in a Dutch population and patient groups (Hoekstra et al., 2008), the total mean score for women was 102.93 (SD= 11.50) and for men 105.66 (SD= 10.99) in the general population. The same study found that the Dutch AQ is a reliable and valid questionnaire for assessing individual differences in autistic traits. The Dutch AQ has a satisfactory internal consistency and test– retest reliability (Hoekstra et al., 2008). In the current research, a Cronbach’s Alpha of α= .910 was found for mothers, and for fathers α= .912.
Behavioral coding
In each interaction, infants and parents’ gaze direction, vocalizations and facial expressions were coded independently of one another. The communicative behaviors were coded by using the computer software Observer XT 9.0, as either point events (frequencies, events that occur at a specific point in time without duration) or state events (duration, events with a start and end time). For the coding scheme, see Table 1 in Appendix A. Coding was done by a group of 6 master students, trained in the use of Observer. Each video was coded by two coders, separately for infant and parent.
Inter-rater reliability was measured on 20% of the 131 coded interactions. The degree of agreement among coders was reached.
Parent-infant Synchrony Interpersonal synchrony between parent and infant was measured by focusing on emotional communication, namely the visual attention (gaze), emotional responses (positive and negative facial expressions) and vocalizations. By using time-window analysis
procedures of co-occurrences, behavior-related relationships (synchrony) can be identified (Chorney et al. 2010; Yoder & Tapp, 2004). First, the behaviors (gaze, facial expressions and vocalizations) of the two interactors were defined and micro-coded on a moment-by-moment basis. Second, these behaviors were examined for the presence of temporal co-occurrence. Specifically, in a short time window, behavior of one person is examined for the presence of the same behavior from the another person at the same moment (Yoder & Tapp 2004). Using the Observer XT 9.0 (Noldus, 2009), two variables have been combined by selecting one variable during another variable. These combined variables have been imported in SPSS as a new variable, namely the synchrony of the selected behavioral variables. Firstly, this study looked at synchrony of gaze (visual synchrony), thus to what extent is the infant gazing at the mother while the mother is gazing at the infant in the same moment. Secondly, the synchrony of positive and negative facial expressions (affective synchrony, either positive or negative affect synchrony) was looked at, thus to what extent do parent and infant share a similar facial
expression in the same moment. Last, the synchrony of vocalizations (vocal synchrony) was looked at, thus, to what extent the infant vocalizes at the same moment when the parent is verbalizing.
Analysis Strategy
All the AQ data gathered in Qualtrics was imported in the statistical computer program IBM SPSS Statistics 22.0. The mean scores of the mothers and fathers separately were computed to measure the level of socio-communicative functioning of the mothers and fathers. All the observational data gathered in the Observer XT 9.0 was imported in SPSS. To prepare the
observational data for statistical analyses, the differences in duration of the observation (a range from 81 to 141 sec) had to be controlled for. In order to do so, proportions were computed for the state events (gaze and facial expressions) and corrected frequencies were computed for the point events (gaze, facial expressions and vocalizations). To make the proportions, the duration of the behavior of interest was divided by the total duration of the observation. To make the corrected frequencies, the frequency of interest was divided by the real duration of the observation, multiplied by the expected length of the observation (120 sec). Next, screenings on missing values of the AQ (total score on AQ: two missing) and observational data (two measurements missing in each variable) showed that missing were completely at random, Mcar test χ²(20) = 15,175, p = 0.766 (see Table 2 in Appendix B). Using SPSS, standardized residuals for the variables were computed to check for univariate outliers. One outlier was found in the variable synchrony of positive facial expressions. This value was corrected for by adjusting the value to the closest value +1. Checking for normality has been done by
looking at the skewness and kurtosis/standard error. Skewness ranged from -.99 to 4.05 and kurtosis ranged from -.69 to 17.47. For the values and SE see Table 3 in Appendix 3. The distributions for proportion of gaze for mothers, and frequency of gaze and positive facial expressions for mothers were not skewed. For kurtosis, the distributions of proportion for both parents for gaze and positives facial expressions and frequency for both parents for gaze and vocalizations have mesokurtic distributions, matching a normal distribution. Also, the distribution of positive facials expressions for mothers has a mesokurtic distribution. All the values of skewness and kurtosis can be found in the Appendix C. Because the distribution for both proportion and frequency of synchrony of negative facial expression in mothers and fathers were highly different from normality, a dichotomous variable was created, consisting of two groups, one for the presence of negative facial expressions and one for the absence of negative facial expressions.
To explore the first hypothesis of this current research, namely that a relation exists between parents’ level of socio-communicative functioning and the levels of parent-infant visual, affective and vocal synchrony, the following variables were used: mean AQ score for mothers and fathers and parent-infant visual, affective and vocal synchrony during the dyadic interactions. Because violating the assumption of normality for the data, in order to explore the main hypothesis, a Spearman
correlation, a non-parametric version of the correlation coefficient (De Vocht, 2013), was conducted to find a relation between parents’ level of socio-communicative functioning and any of the dimensions of synchrony, namely the visual, affective and vocal. The second hypothesis, expecting that fathers show more autistic traits and thus lower synchronizing of the visual, affective and vocal dimensions will show stronger associations with paternal interaction, was explored by conducting an one way analysis of variance (ANOVA). In this way, the level of socio-communicative functioning and the differences in level of parent-infant visual, affective and vocal synchrony between mothers and fathers were explored (between-subject). The ANOVA is considered a robust test against the normality assumption and can tolerate data that is non-normal (skewed or kurtotic distributions) (Rogan & Kesselman, 1977). To explore the dichotomous variable of parent-infant negative affect synchrony of mothers and fathers, a Chi square test was performed to test the differences between mothers and fathers. For the last hypothesis, expecting that the level of parent-infant synchrony among same-gender dyads would be higher in terms of longer co-occurrences between the partners’ behavior, an one way variance analysis (ANOVA) was conducted in order to explore the differences in level of visual, affective and vocal synchrony between same gender parent-infant dyads. For all the analysis, a p-value smaller than .05 meant a statistical significance.
Results Descriptive statistics
First, the mean differences of mothers and fathers on the experimental variables were
explored. Table 4 displays the average scores for both mothers and fathers’ AQ and separate subscales, and parent-infant visual, affective and vocal synchrony. Synchronies were measured both as
proportions (i.e., duration of the selected behavior divided by the total length of the observation) and number of occurrences (frequency). Fathers (M = 102,53; SD = 19,1; MIN = 63; MAX = 141) scored a higher mean score on the AQ than mothers (M = 97,27; SD = 17,99; MIN = 62; MAX = 136). A study by Hoekstra, Bartels, Cath & Boomsma (2008), investigating the AQ in a general Dutch population, found similar mean scores for men (M = 105,55; SD = 10,99) and women (M = 102,93; SD = 11,50). In addition, fathers score higher on every separate subscale of the AQ (Social skills, Attention switching, Communication and Imagination), except for the subscale Attention to detail. In general, fathers show more autistic traits (Fathers total score: 102.53 and mothers total score: 97.27) and thus, more impairments in the socio-communicative functioning. This was as expected
beforehand, because both sub-clinical autistic traits and ASD are more prevalent in male than female subjects (Amaral, Schumann & Nordahl, 2008; Baron-Cohen et al, 2001, 2011; Constantino & Todd, 2003). However, this difference was not significant: t (63)= .914, p = .364. Mothers have a higher mean score on all dimensions of synchrony, except for frequency of visual synchrony. Infants’ interactions with mothers are characterized by longer and more frequent positive and negative affect synchrony and vocal synchrony during their interactions whereas interactions with fathers are characterized by more frequent visual synchrony. Also, there is a longer visual synchrony during mothers-infant interactions, but father-infants have a more frequent visual synchrony.
Tabel 4
Descriptive statistics of AQ and synchrony
Mothers Fathers
M SD Min. Max. M SD Min. Max.
AQ Social Skills 18.76 5.71 11 33 19.13 6.12 10 34 Attention switching 20.36 4.77 11 31 22.22 4.54 15 32 Communication 17.06 4.09 10 26 18.66 5.18 10 28 Attention to detail 23.97 4.38 14 32 23.13 5.22 12 35 Imagination 12.12 3.55 11 24 19.41 3.46 12 26 Total score 97.27 17.99 62 136 102.53 19.1 63 141 Synchrony proportion Visual 77.35 .19 .37 1 73.59 .22 .18 .98 Pos. affect 21.49 .18 .02 .72 18.39 .19 0 .75 Neg. affect 0.79 .02 0 .08 .06 .002 0 .01 Synchrony frequency Visual 9.91 5.76 2.94 22.82 10.04 5.81 2.94 25.83 Pos. affect 13.56 9.79 .99 38.5 11.7 12.09 0 58 Neg. affect Vocal 10.35 0.95 2.21 8.95 0 0 35.02 9.91 6.59 .07 5.59 .24 0 0 21.41 1.22 Note. AQ= Autism Questionnaire is from Baron-Cohen, S., Hoekstra, R. A., Knickmeyer, R., & Wheelwright, S. (2006), Pos. affect= positive affect, Neg. affect = negative affect
Main analysis
Hypothesis 1. The main hypothesis explored whether a relation existed between parents’ level of socio-communicative functioning and the levels of parent-infant visual, affective and vocal
synchrony. In order to do so, a Spearman Rho’s correlation was conducted. A significant positive relation between Attention to detail and Positive affect Synchrony during mother-infant interactions was found, for both proportion (Rs = .476, p = .006) and frequency (Rs = .407, p = .021). No other significant relations between parents’ level of socio-communicative functioning and the rest of the dimensions of parent-infant synchrony were found (see Table 5). This means that the self-reported level of socio-communicative functioning of these scales of mothers and fathers did not have an influence on the level of observed parent-infant synchrony during the interaction with their infant. Because no significant correlation was found, the regression analysis planned to be done was not carried out.
Table 5
Spearman correlation of parental level of socio-communicative functioning and parent-infant synchrony
Synchrony proportion Synchrony frequency Visual Pos.
affect affect Neg. Visual affect Pos. affect Neg. Vocal Social Skills Mother -.112 .068 .093 .164 .048 .093 .063 Father .212 -.161 .177 -.190 .177 -.223 -.109 Attention Switching Mother -.062 .212 -.076 .262 .244 -.076 -.209 Father -.084 -.057 .215 -.051 .066 .215 -.083 Communica- tion Mother .019 .238 -.062 .066 .180 -.062 -.061 Father .190 -.071 .070 -.243 .008 .070 -.191 Attention to detail Mother -.045 .476* -.287 .184 .407* -.287 -.126 Father -.281 .159 .098 .278 -.064 .098 .175 Imagination Mother .045 .033 .152 .063 .022 .152 -.072 Father .019 -.070 .097 -.084 -.097 .097 .037 Total AQ score Mother .002 .291 -.089 .106 .259 -.089 -.079 Father .047 -.051 .103 -.067 -.111 .103 -.122
Note. * = p < .05, AQ= Autism Questionnaire, Pos. affect= positive affect, Neg. affect = negative affect.
Hypothesis 2. For the second hypothesis, the possible existence of significant differences in level between mothers’ and fathers’ level of socio-communicative functioning and in level of parent-infant visual, affective and vocal synchrony was explored by conducting an one way analysis of variance (ANOVA), using parents’ gender as the between variables. Because the assumption of homogeneity of variances has been violated for parent-infant synchrony of both proportion and frequency of negative affect synchrony and vocal synchrony, a Welch’s test has been conducted for these dimensions. No overall main effect for parents gender was found for socio-communicative functioning, F(1, 64) = .835, p = .364. This means that there is no significant difference in level of socio-communicative functioning between mothers and fathers. In addition, no significant differences in level was found for the separate subscales of the AQ, namely Social skills, Attention switching, Communication, Attention to detail and Imagination between mothers and fathers. For the dimensions of parent-infant synchrony, a significant difference was found for gender of parent on parent-infant negative affect synchrony, both for the proportional scores F (1, 31) = 5,066, p = .031, and the
frequency scores, F (1, 31) = 5,066, p = .031. Also, a significant difference was found for the gender of frequency of parent-infant vocal synchrony F (1, 51) = 4,103, p = .048. This means that there is a significant difference between mothers and fathers for parent-infant negative affect synchrony and vocal synchrony during their interaction with their infants. It can be concluded that mother-infant interactions are characterized by longer and more frequent negative affect synchrony and vocal synchrony during their interaction, based on the higher mean score of mothers on these dimensions of synchrony as described in the descriptive statistics earlier. In addition, during parent-infant
interactions, mother and infant gaze to each other longer, but the visual synchrony is more prevalent with father. No overall main effect for parent gender was found for the other dimensions of synchrony, namely visual and positive affect. These analysis are reported in Table 6.
Table 6
ANOVA analysis of level of parental socio-communicative functioning and parent-infant synchrony One way Anova Welch
Df F Df F AQ Social Skills 1, 63 .139 Attention Switching 1, 64 .209 Communication 1, 64 .152 Attention to Detail 1, 64 1.181 Imagination 1, 64 .013 Total score 1, 63 .835 Synchrony proportion Visual 1, 64 .540 Pos. affect 1, 64 .452 Neg. affect 1, 31 5.066* Synchrony frequency Visual 1, 64 .009 Pos. affect 1, 63 .459 Neg. affect 1,31 5.066* Vocal 1, 51 4.103*
Note. * = p < .05, AQ= Autism Questionnaire, Pos. affect= positive affect, Neg. affect = negative affect.
In order to deal with the issue of violation from normality for both proportion and frequency of parent-infant negative affect synchrony, a dichotomous variable was created, consisting of two groups: one group for the presence of one or more moments of negative affect synchrony and a group for absence of negative affect synchrony. To examine the significance of the differences of mothers and fathers between the groups, a Chi square test was performed. A significant effect for gender on both the proportion X²(1) = 6,146, p= .013, and frequency X²(1) = 6,146, p= .013 of parent-infant
negative affect synchrony was found. These analysis are reported in Table 7 in Appendix D. This means that for both proportion and frequency, there is a significant relation between gender and negative affect synchrony. Mothers have significantly longer and more frequent negative affect synchrony with their infant during interaction.
Hypothesis 3. For the last hypothesis, the differences in level of parent-infant visual, affective and vocal synchrony between same gender dyads were explored by conducting an one way variance analysis (ANOVA), using same gender dyads (yes/no) as the between variables. First, the differences in level of same gender and not same gender dyads was explored (two groups). No overall main effect was found for the same gender dyads (see Table 8). Second, the differences in level of female-female, male-male and no same gender dyads were explored (three groups). Because the assumption of homogeneity of variances has been violated for the three group parent-infant synchrony of both proportion and frequency of negative affect synchrony and proportion of visual synchrony, a Welch’s test has been conducted for these dimensions. No overall main effect was found. This means that there is no significant difference in level of parent-infant synchrony during the interaction of same gender dyads or no same gender dyads.
Table 8
ANOVA analysis for same gender dyads and parent-infant synchrony
Two groups Three groups Welch’s test
Df F Df F Df F Synchrony proportion Visual 1, 63 1.077 2, 32 1.498 Pos. affect 1, 63 1.016 2, 62 .720 Neg. affect 1, 63 .761 2, 26 2.810 Synchrony frequency Visual 1, 63 .006 2, 62 .405 Pos. affect 1, 62 .459 2, 61 .317 Neg. affect Vocal 1, 63 1, 63 1.205 .761 2, 62 .667 2, 26 2.810 Note. Pos. affect= positive affect, Neg. affect = negative affect.
Discussion
This current research aimed to investigate the role of parental socio-communicative
functioning in parent-infant synchrony of emotional communication behaviors during a face-to-face interaction at 4 months of age. As hypothesized, mothers and fathers are equally capable of engaging in synchronal behaviors of visual, affective and vocal with their infants (Feldman, 2003). Also,
father-infant visual synchrony is more prevalent but shorter than during mother-father-infant interactions. However, results suggested that mothers and infants have longer and more frequent negative affect synchrony and more frequent vocal synchrony. Besides, no significant differences in the level of
socio-communicative functioning between mothers and fathers were found. The trend found in our sample however, is in line with previous research showing that both sub-clinical autistic traits and ASD are more prevalent in male than female subjects (Amaral, Schumann & Nordahl, 2008; Baron-Cohen et al, 2001, 2011; Constantino & Todd, 2003). Unexpectedly, our results did not support the hypothesis of the existence of a relation between the level of parental socio-communicative functioning and the level of parent-infant vocal, affective or visual synchrony during the interactions with their infant.
Parental Socio-communicative functioning Although no differences in the level of socio-communicative functioning between mothers and fathers were found, fathers had a slightly higher mean score on the AQ than mothers. Thus, fathers have more autistic traits, however, this difference is not significant. This can be explained by considering that this study was carried out in the general population. Another study by Hoekstra, Bartels, Cath & Boomsma (2008), investigating the AQ in a general Dutch population, found similar mean scores for men and women. In comparison, this same study found that a high total AQ score (>145) was found to be specific for adults with autism spectrum disorder (ASD). Neither subjects from the general population obtained scores in this segment, while all subjects with ASD scored in this range. The mean scores in the normal population found in this current study, and thus the level of autistic traits, might not be severe enough to cause impairments in socio-communicative functioning. A high Cronbach’s Alpha for mothers and for fathers was found.
Parent-infant Synchrony Research, mostly done on mother-infant synchrony, shows that interpersonal synchrony is associated with better cognitive processing, school adjustment (Harrist, Pettit, Dodge & Bates, 1994), empathy (Feldman, 2007), symbolic play and internal state speech (Feldman & Greenbaum, 1997), attachment security (Lundy, 2002, 2003) and more higher cognitive and behavioral outcomes for the child (Leclère et al, 2014). During the infants’ first year of life, interpersonal synchrony is often displayed by gaze, facial expressions and vocalizations during face-to-face interactions between parent-infant. As children age, interpersonal synchrony is also displayed by increased child initiation and turn taking and synchrony occurs in parent-infant-object triadic coordination’s, sequential dependence of parent reciprocity and the use of symbols in words and gestures of the infant (Feldman, 2007).
In line with previous studies (Feldman, 2003; Weinraub and Frankel 1977), results of this study show that mothers and fathers are equally capable of engaging parent-infant synchrony on the visual, affective and vocal modalities. During the interactions between mothers and infant, there was a slightly longer and more frequent visual, positive and negative affect and vocal synchrony than during interactions between fathers and infant. However, as expected, no significant differences in level of
parent-infant visual synchrony and positive affect synchrony were found between mothers and fathers. Colonnesi et al (2012) found that infants have a more positive emotional communication with their mother, which is the same in findings of this current study, which imply that during the interaction between mother and infant there is a slightly higher and longer positive affect synchrony. However, interestingly, this study found that mothers have more frequent and a longer negative affect synchrony with their infants during these interactions as well. This could be explained by the findings of earlier studies (Feldman, 2003), which show that mothers’ interaction with the infant focusses on micro-level face-to-face signals and exchange of these signals is more socially oriented, while the interaction with their father has more focus on play and high, quick peaks of positive emotions. Because the interaction with mothers is more socially oriented and focusses on face to face signals, mothers might be more helpful to the infant to self-regulate negative emotionality (Gianino & Tronick,1988; Gordon & Feldman, 2008). This supports the theory that each interaction with the parents creates its own communicative patterns, that will organize the infants’ later behavior and engagement with the world (Hsu & Fogel 2003; Tronick, 2003; Tronick & Beeghly, 2011). Besides, during mother-infant
interactions, a more frequent vocal synchrony was found, which could be explained by the findings of Brundin, Rodholm & Larsson (1988), which imply that mothers tend to vocalize more than fathers.
In contrast to the findings of Feldman (2007), no differences in level of parent-infant
synchrony was found in same-gender parent-infant dyads. These contrasting findings can be a result of the differing sample sizes. The study of Feldman used 202 participants and the current study 65 participants. When the sample size is smaller, the change for significance decreases (Baarda, 2009). This effect could also be due to the low statistical power.
Parental socio-communicative functioning and parent-infant synchrony A significant positive relation between Attention to detail and Positive affect synchrony during mother-infant interactions was found, for both proportion and frequency. This means that when mothers pay more attention to details, higher levels of positive affect synchrony was found during mother-infant interactions. Attention to details, in terms of parental attention to detailed emotional signals in the infants’ face and behavior, is likely to be an important factor in being able to react sensitive and attentive to the
emotional signals of the infant and thus, engaging in parent-infant synchrony. That women are better than men at recognizing subtle emotional expressions is supported in a meta-analysis by Thompson & Voyer (2014). Woman, compared to man, show more decoding accuracy of infants’ detailed emotional expressions from photographs (Proverbio, Matarazzo, Brignone, Del Zotto & Zani, 2007). This gender difference can be explained by evolutionary perspectives based on the mothers near-universal
responsibility for raising the child (Babchuk, Hames, & Thompson, 1985). The primary caretaker theory contends that mothers, as primary caretakers, will display evolved adaptations that will increase the chance of survival of their children. In this context it is the fast and accurate decoding of facial
affect, an important factor in communication, especially in preverbal infants (Hampson, Anders & Mullin, 2006).
This current study found no other significant relations between the level of
socio-communicative functioning of parents and the level of visual, affective or vocal synchrony during the interaction with their infant. Due to the considerably low, not clinical, scores of mothers and fathers on the AQ, it is not possible to give a clear representation if low socio-communicative functioning of parents actually has an influence on the synchrony during the interaction between parent-infant. Parent-infant interactions have been widely acknowledge to play a crucial role in the early development of the infant. Infants get introduced to- and learn about the social world through the interactions with their parents. This interaction is seen as a complex system in which not only the parent but also the infant, influences on- and is influenced by the interaction (Tronick, Als, Adamson, Wise & Brazelton, 1978). During this interaction, they connect through a relationship that allows a multidirectional flow of information and reciprocal responses to verbal and nonverbal signals. This is described as interpersonal synchrony, a relation that exist when two or more events occur at the same time and cohere into a single process (Merriam-Webster Medical Dictionary, 2002). Through
interpersonal synchrony, the infant develops symbol use, empathy and self-regulation and synchrony lays the foundation for the infants’ later capacity for engaging social interaction throughout life (Feldman, 2007). The level of parental socio-communicative functioning may have an influence on parent-infant synchrony and thus, the development of important skills for the infant. This emphasizes the necessity for research on the influence of socio-communicative functioning of parents on the parent-infant synchrony during interactions to better define the role of parents in the development of social understanding in early infancy.
Further research suggestions To answer the hypothesis that a relation exists between the level of socio-communicative functioning of parents and the level of parent-infant visual, affective and vocal synchrony, this study needs to be conducted in a larger and wider general population with more variation in the participants. Since autism is identified as a spectrum disorder, using a larger sample will allow more differences in degree of impairments in the characteristics of ASD, which may result in more variation in level of socio-communicative functioning of the participants.
Besides, healthy developing parent-infant dyads do not achieve perfect synchrony at all times (Gianino & Tronick,1988) and each interaction partner plays a role in restoring synchrony during interactions; even young infants have coping behavior for repairing mismatch during interactions (Tronick, Als & Brazelton, 1977). Thus, in order to conduct a clear and broader image about the synchrony during a parent-infant interaction, the capability of the infant to engage in synchrony with their parents has to be investigated too. From birth on, parent and infant build a relationship and influence each other during interactions. This shapes their interaction and builds the foundation for the
infants’ future relationships. Thus, early deficits in the infant’s socio-communicational skills may have an influence on the parents’ pattern of responding to the infant, which could increase early social competence impairments and lead to an abnormal developmental trajectory (Dawson, 2008; Elsabbagh and Johnson, 2007, 2010). Extensively it has been shown that ASD is not caused through bad
parenting. However, the influence of the socio-communication skills of parents and infants on the interaction may contribute to an abnormal social developmental trajectory and, or, can be used as a sensitive detector of early social abnormalities of the infant (Elsabbagh et al., 2014). It is likely that the parent-infant interpersonal synchrony may be disrupted with an infant who will later on develop autism and this abnormal social development of the infant could affect parents’ interactive patterns (Cohen et al, 2013). It is recommended that this will be included as well in further research to social predisposition and synchrony in parent-infant interactions.
Limitations regarding the current study A few limitations of this research should be noted. First, the distribution for all modalities of synchrony were highly different from normality, so the results on synchrony need to be interpreted carefully. A second limitation of this research should be noted regarding the sample size. A limitation of small studies is that it can result in false-positives (Hackshaw, 2008) and thus the results need to be interpreted carefully. Besides, using a larger sample than the current one could have resulted in significant results due to smaller effect sizes, so there is a necessity to test these hypothesis more sharply in future research. Last, the majority of the parents included in this research were high educated and could decide for themselves if they wanted to join this study, which can result in little variability and may not be representative for the Dutch population. Further research should include a more varied sample and for comparison, a clinical population.
Clinical implication Research on synchrony in early face-to-face interaction between infants and parents and socio-communicative functioning of parents contributes to our knowledge on later socio-communicative development. Firstly, because the early parent-infant synchrony in dyadic interactions sets the basis and may predict later triadic interaction (starting at 8 months of age of the infant) in which infants become able to communication through their emotions about an external event or object (Colonnesi et al., 2008; Messinger & Fogel, 1998). Secondly, there is a necessity to better understand the role of social predispositions of parents. Low socio-communicative functioning of parents might be an early indicator of an infant’s genetic vulnerability for ASD (Constantino & Todd, 2005). Besides, low socio-communicative functioning of the parent may have an poor influence on synchrony and thus, the development of critical skills for the infant. To provide earlier interventions, based on strengthening the first social-emotional communication, there is the necessity to anticipate the detection of autistic traits and socio-communicative problems in early infancy.
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