The role of person familiarity in young infants' perception of emotional expressions

This research investigated the role of person familiarity in the ability of 3.5-month-old infants to recognize emotional expressions. Infants (N = 72) were presented simultaneously with two filmed facial expressions, happy and sad, accompanied by a single vocal expression that was concordant with one of the two facial expressions. Infants' looking preferences and facial expressions were coded. Results indicated that when the emotional expressions were portrayed by each infant's own mother, infants looked significantly longer toward the facial expressions that were accompanied by affectively matching vocal expressions. Infants who were presented with emotional expressions of an unfamiliar woman did not. Even when a brief delay was inserted between the presentation of facial and vocal expressions, infants who were presented with emotional expressions of their own mothers looked longer at the facial expression that was sound specified, indicating that some factor other than temporal synchrony guided their looking preferences. When infants viewed the films of their own mothers, they were more interactive and expressed more positive and less negative affect. Moreover, infants produced a greater number of full and bright smiles when the sound-specified emotion was "happy," and particularly when they viewed the happy expressions of their own mothers. The average duration of negative affect was significantly longer for infants who observed the unfamiliar woman than for those who observed their own mothers. These results show that when more contextual information-that is, person familiarity-was available, infants as young as 3.5 months of age recognized happy and sad expressions. These findings suggest that in the early stages of development, infants are sensitive to contextual information that potentially facilitates some of the meaning of others' emotional expressions.     

Depressed Mothers' Touching Increases Infants' Positive Affect and Attention in Still-Face Interactions

The effects of depressed mothers' touching on their infants' behavior were investigated during the still-face situation. 48 depressed and nondepressed mothers and their 3-month-old infants were randomly assigned to control and experimental conditions. 4 successive 90-sec periods were implemented: (A) normal play, (B) still-face-no-touch, (C) still-face-with-touch, and (A) normal play. Depressed and nondepressed mothers were instructed and shown how to provide touch for their infants during the still-face-with-touch period. Different affective and attentive responses of the infants of depressed versus the infants of nondepressed mothers were observed. Infants of depressed mothers showed more positive affect (smiles and vocalizations) and gazed more at their mothers' hands during the still-face-with-touch period than the infants of nondepressed mothers, who grimaced, cried, and gazed away from their mothers' faces more often. The results suggest that by providing touch stimulation for their infants, the depressed mothers can increase infant positive affect and attention and, in this way, compensate for negative effects often resulting from their typical lack of affectivity (flat facial and vocal expressions) during interactions     

Beyond the Face: An Empirical Study of Infant Affective Configurations of Facial, Vocal, Gestural, and Regulatory Behaviors

This article evaluates the extent to which infants' expressive modalities of face, gaze, voice, gesture, and posture form coherent affective configurations and whether these configurations are related to specific interactive contexts. 50 6-month-old infants and their mothers were videotaped in Tronick's Face-to-Face Still-Face Paradigm. The infants' gaze, voice, gestures, self-regulatory, and withdrawal behaviors were coded with the Infant Regulatory Scoring System (IRSS). The infants' facial expressions were coded with Izard's AFFEX system. Contingency analyses of IRSS behaviors and AFFEX expressions revealed 4 distinct affective configurations: Social Engagement, Object Engagement, Passive Withdrawal, and Active Protest. These affective configurations were differentially distributed among the different interactive contexts of the Face-to-Face Still-Face Paradigm. It is suggested that behaviors and facial expressions are fundamental expressive units flexibly organized into configurations that convey messages about the infant's internal state and intentions. Furthermore, it is hypothesized that the basic units of the infant's experience are these distinct affective configurations of emotion and behavior.     

Affective Influences on Startle in Five-Month-Old Infants: Reactions to Facial Expressions of Emotion

Convergent methodologies from studies of fear-potentiated startle in animals and studies of affective modulation of reflex blinks in humans were adapted in order to investigate infants' sensitivity to affective information conveyed by facial expressions of emotion. While 5-month-old infants viewed photographic slides of faces posed in happy, neutral, or angry expressions, a brief acoustic noise burst was presented to elicit the blink component of human startle. Blink size was augmented during the viewing of angry expressions and reduced during happy expressions. Infants did not show marked changes in behavioral reactions to the positive, neutral, and negative slides, although motor activity was slightly reduced during negative slides. Results suggest that, by 5 months, infants react to affective information conveyed by unfamiliar human faces. Potential mechanisms mediating the influence of affective stimuli on reflex excitability are considered.     

Infants' perception of dynamic affective expressions: do infants distinguish specific expressions?

Seven-month-old infants' perception of positive (happy, interested) and negative (angry, sad) affective expressions was investigated using a preferential looking procedure (n = 20 in each of 6 conditions). The infants saw two videotaped facial expressions and heard a single vocal expression concordant with one of the facial expressions. The voice on the soundtrack was played 5 s out of synchrony with the ongoing affective visual display. Infants participated in one of six conditions (all possible pairs of the four expressive events). Infants' visual fixations to the affectively concordant and affectively discordant displays were recorded. Infants looked longer at the affectively concordant displays than at the affectively discordant displays in all conditions except the happy/sad and interested/sad conditions. For these two comparisons, facial discrimination was demonstrated by the infants' preferential looking at happy and interested expressions compared to the sad expression. Thus, 7-month-old infants discriminate among happy, interested, angry, and sad expressions, demonstrating differentiation among specific, dynamic expressions. The results are discussed in terms of the information specifying facial and vocal affect and the possible role of familiarity in learning to differentiate among affective expressions during infancy.     

Infants' affective responses in the strange situation: effects of prematurity and of quality of attachment

20 full-term and 20 preterm infants and their mothers were videotaped in the Strange Situation, and the security of their attachment relationships was later determined. Each episode was subsequently divided into consecutive 15-sec intervals, during each of which ratings of facial expressions were performed. From these ratings several summary dimensions of affect were derived (e.g., affective peak and range during all episodes, latency and rise time for onset of distress during separation episodes, and recovery time during reunions). Term and preterm infants did not differ from one another in either the security of attachment or their affective expression and regulation. When groups were combined, patterns of affective expression were significantly different for infants classified as insecure-avoidant, insecure-ambivalent, and securely attached, as well as for group B1 + B2 infants compared to group B3 + B4 babies. The findings indicated that attachment-related affect may reflect an affect continuum that underlies certain mother- and stranger-directed behaviors in the Strange Situation, but that not all aspects of reunion behavior can be predicted by prior separation reactions.     

Generalized Discrimination of Positive Facial Expressions by Seven- and Ten-Month-Old Infants

The ability of 7- and 10-month-old infants to generalize their discrimination of facial expressions lacking featural consistency was investigated in a series of 4 experiments. Infants were habituated to models posing either prototypically positive displays (e.g., happy expressions) or positive expression blends (e.g., mock surprise). They were then tested for their ability to recognize a positive expression on the face of a novel model and to discriminate positive and negative facial expressions. Only in Experiment 1, in which infants were familiarized to a mix of happy and surprised facial expressions, did 10-month-olds demonstrate generalized discrimination of positive affect. When positive blends or happy expressions alone served as familiarization stimuli, both 7- and 10-month-old infants failed to dishabituate to a change in affective tone. 7-month-olds, in particular, showed consistent recovery of looking to the introduction of novel models. The pattern of results suggests that it is not until sometime after 7 months of age that dependence on the presence of expression-specific features for affect recognition and discrimination diminishes. By 10 months of age, however, infants are beginning to recognize the affective similarity of familiar positive facial expressions.     

The rhythmic structure of mother-infant interaction in term and preterm infants

The purpose of this study was to quantify social interaction rhythms in 3- and 5-month-old term and preterm infants and their mothers. Infant-mother dyads were videotaped in a 3-min face-to-face paradigm. For each second of the interaction, separate scores were assigned to infant and mother indicating levels of affective involvement, creating 2 180-sec time series. Spectral and cross-spectral techniques were used to quantify periodicities in each member of the dyad and to estimate the synchrony or coherence of interactional rhythms between each infant and mother. Results showed the existence of periodicities in the behavior of each infant and mother at 3 and 5 months, with most subjects showing spectral peaks between .022 and .10 Hz. Increases from 3 to 5 months in behavioral periodicities were found for infants and mothers as well as for the coherence between infant-mother dyads. Term dyads showed higher coherence than preterm dyads at both 3 and 5 months. Term infants more often led the interaction at both ages. These results were taken as evidence that behavioral periodicities, which may be biologically based, underlie early mother-infant interaction and provide a temporal structure for the organization of cognitive and affective experience. Differences in synchrony between term and preterm infants may explain later reported differences in language between these groups.     

“Dancing” Together: Infant–Mother Locomotor Synchrony

Pre-mobile infants and caregivers spontaneously engage in a sequence of contingent facial expressions and vocalizations that researchers have referred to as a social “dance.” Does this dance continue when both partners are free to move across the floor? Locomotor synchrony was assessed in 13- to 19-month-old infant–mother dyads (N = 30) by tracking each partner’s step-to-step location during free play. Although infants moved more than mothers, dyads spontaneously synchronized their locomotor activity. For 27 dyads, the spatiotemporal path of one partner uniquely identified the path of the other. Clustering analyses revealed two patterns of synchrony (mother-follow and yo-yo), and infants were more likely than mothers to lead the dance. Like face-to-face synchrony, locomotor synchrony scaffolds infants’ interactions with the outside world.     

The development of social referencing

The development of social referencing in 40 infants aged 6-9, 10-13, and 14-22 months was investigated in this study. Social referencing was defined broadly to include children's looks toward parents, their instrumental toy behaviors, affective expressions, and other behaviors toward parents. Children's looks at parents were more selective with increasing age, with older infants preferring to look directly at their parents' faces and younger infants showing no preference for looks to faces over looks elsewhere at the parent. Younger infants looked most often when their parents expressed positive affect, whereas older infants looked most often when parents displayed fearful reactions toward a stimulus. Evidence of a behavioral regulatory effect on instrumental toy behaviors was found only among infants 10-13 months of age. However, only infants older than 14 months of age inhibited touching the toy until after referencing the parent. On some measures these older infants showed a preference for toys associated with fearful messages. Affective expressions were in line with positive and negative behavior toward toys. No support for mood modification or simple imitation as explanations for the effects was found. Results indicated that the looking behavior of younger children may function differently than that of older children, and that social referencing involves a number of component skills that develop during the end of the first year and throughout the second year of life.     

Emotional Determinants of Infant-Mother Attachment

The present study examined the assumption that emotion-related characteristics of mothers and infants contribute to the development of infant-mother attachment in the first year of life. Mothers' emotion and personality characteristics were assessed with expressive-behavior ratings and self-report scales. Infant characteristics were measured by emotion and temperament questionnaires (mother report) and objective coding of facial expressions of emotions. Attachment classifications were determined by means of the Strange Situation procedure, and a continuous-variable index of attachment security was derived by a discriminant function procedure. Mothers' emotion experiences, expressive behaviors, and personality traits were significant predictors of the level of security of the infant-mother attachment. Infants' expressive and temperamental characteristics as rated by their mothers were also significant predictors of attachment security.     

Intermodal Perception of Happy and Angry Expressive Behaviors by Seven-Month-Old Infants

2 studies were conducted to examine the roles of facial motion and temporal correspondences in the intermodal perception of happy and angry expressive events. 7-month-old infants saw 2 video facial expressions and heard a single vocal expression characteristic of one of the facial expressions. Infants saw either a normally lighted face (fully illuminated condition) or a moving dot display of a face (point light condition). In Study 1, one woman expressed the affects vocally, another woman expressed the affects facially, and what they said also differed. Infants in the point light condition showed a reliable preference for the affectively concordant displays, while infants in the fully illuminated condition showed no preference for the affectively concordant display. In a second study, the visual and vocal displays were produced by a single individual on one occasion and were presented to infants 5 sec out of synchrony. Infants in both conditions looked longer at the affectively concordant displays. The results of the 2 studies indicate that infants can discriminate happy and angry affective expressions on the basis of motion information, and that the temporal correspondences unifying these affective events may be affect-specific rhythms.     

Manual actions of nine- to fifteen-week-old human infants during face-to-face interaction with their mothers

This paper presents evidence that the manual actions of infants as young as 9 weeks of age may occur in relation to their facial expression, gaze direction, and vocalization. 28 full-term, healthy infants were observed during a 2-min spontaneous face-to-face interaction with their mothers. Videotapes were coded in real time using the following categories of manual action: POINT, SPREAD, CURL, and GRASP. Facial expressions, gaze direction, and vocalizations also were coded for each infant. All of the infants displayed CURL, 20 infants displayed SPREAD, 18 POINTED, and 11 showed GRASP. Right/left differences appeared for the categories CURL, SPREAD, and GRASP, but not for POINT. Hand action was systematically organized into sequences with other infant action. POINT occurred before or after mouthing and vocalization, CURL during vocalization, and SPREAD when the baby was looking away from the mother. The results are discussed in relation to their implications for the ontogeny of nonverbal communicative gestures.     

Infants' Instrumental Use of Their Mothers to Achieve Their Goals

In order to investigate very young children's active contribution to managing interaction with others, we examined 6–13-month-old infants' instrumental use of their mothers to reach goals. We examined the idea that infants are already involved at 6 months in managing interaction with adults, with rapidly increasing instrumental use of mothers between 6 and 13 months. 64 mother-infant pairs were videotaped during structured episodes in which the investigator instructed the mother to challenge the infant to use her instrumentally to get access to or to work a toy. Already at 6 months of age, infants used their mothers instrumentally in 36% of the episodes. The amount of infants' instrumental use of their mothers increased to 67% of episodes at 9 months and continued increasing to 78% of the episodes by 13 months. These results suggest early and rapid development of infants' management of joint activities from as early as the middle of the first year of life.     

Maternal Responses to Infant Distress: Linkages Between Specific Emotions and Neurophysiological Processes

Objective. The goals of the current article were to test the presence of an association between mothers’ neural activity (measured by frontal cortical alpha asymmetry) and their specific emotions (measured by observed facial expressions) in response to infant distress and the moderation of this relation by mothers’ appraisal processes (measured by sense of parenting efficacy). Design. Mothers of 5- to 8-month-olds (n = 26) watched videos of their own infants expressing distress while their brain activity was recorded via electroencephalogram and their facial expressions were videotaped for later microcoding. Mothers also completed a questionnaire measure of parenting efficacy. Results. Greater neurophysiological withdrawal in response to infant distress videos, indexed by frontal alpha asymmetry, was associated with longer sad and tense expressions in mothers with average or below average parenting efficacy, but not in those with above average efficacy. Conclusions. Previous research showing that patterns of parents’ brain activity in response to child stimuli are associated with parenting behavior often interpret results in relation to parental emotion, but rarely measure specific concurrent emotions. The current study helps fill this gap in the literature by showing that maternal neurophysiological withdrawal (together with parenting efficacy) was associated with simultaneously measured facial expressions of negative emotion in response to infant distress stimuli.     

Smile production in older infants: the importance of a social recipient for the facial signal

2 studies tested the hypothesis that infant smile production depends on the availability of a social recipient for the facial signal, as well as on appropriate internal events. We examined the effects of attentive and inattentive, familiar and unfamiliar social objects on smile production in 1 1/2-year-old infants outside of social interactions. Like adults, these infants directed a majority of the smiles produced during nonsocial activity to an attentive social object. Overall smiling frequency was much lower when the only potential recipient (the mother) was inattentive, but the effect did not appear to be mediated by negative emotion. Only smiles directed to mother were reduced: nonsocial smiling (at the toys) was not sensitive to mother's inattention, and when an attentive, friendly stranger was present, she was accepted as a substitute target for social smiles. We conclude that an open channel of social communication promotes the outward expression of internal affect in infants.     

Emotion socialization and expressive development in preterm and full-term infants

The expressive behaviors of full-term and preterm infants and their mothers were examined during face-to-face interaction when the infants were approximately 2 1/2, 5, and 7 1/2 months old. Videotapes of the sessions were coded on a second-to-second basis using Izard's discrete emotion coding system. Overall, infants showed a linear increase in positive effect, especially interest and joy, and a corresponding decrease in negative affect, especially pain and knit brow, with age; decrease in negative affect was accounted for largely by the preterm infants. In terms of maternal responses, there was an increase in contingent responding to infant interest expressions and a decrease in contingent responding to infant pain expressions over time, especially in the case of the preterm infant. The data set as a whole was examined further to establish the directionality of influence between mothers and infants in change patterns over time. There was evidence of learning effects in infants as a function of maternal modeling and contingency patterns. Anomalies in maternal responses to preterm infant affect expressions were observed. Mothers of these infants displayed significantly less matching or imitation of their infant's facial expressions, showed random rather than contingent responsiveness to sadness, and a significant ignoring response to infant anger. These differences were attributed to differences in gazing patterns and negative emotion expression in preterm infants. The results are discussed within a framework of emotion socialization that recognizes bidirectionality of influence in the emotional patterns of mothers and infants.     

Activities and Interactions of Mothers and Their Firstborn Infants in the First Six Months of Life: Covariation, Stability, Continuity, Correspondence, and Prediction

Activities of primiparous mothers and infants were observed at 2 and 5 months of age during naturalistic interactions at home. 5 prominent features of mother and infant exchanges in this short-term longitudinal study are described and discussed in the context of 3 models of unique environment-development relations: covariation, stability, continuity, correspondence, and prediction. Generally, mothers' activities did not positively covary at either age, nor did those of infants. Some maternal activities were stable in this time period; some developmentally increased, and some developmentally decreased. Infants' activities were unstable, but most increased over time. Specific mother and infant activities corresponded, and over time mothers and infants influenced one another in specific ways. In the critical period of the first half year, infants appear to be flexible and plastic in their behavioral repertoires and are influenced by their mothers; mothers are somewhat consistent, but they also adapt to the behaviors of their infants.     

Changes in parent-child interaction in response to intervention

Parent-child interactions during the early years form the basis of many types of skill acquisitions, including fine motor and communication skills. Early intervention programmes aimed at promoting the attainments of children with disabilities or learning delays often suggest ways in which parents can interact with their children. The present study examined whether such intervention changes the nature of the parent-child interaction, using two groups of typically developing infants. The mothers of these two groups of prelinguistic children aged 10–12 months and 17–18 months were recorded talking to their infants when playing with a toy and then when asked to encourage their child to play in a particular way. Analyses of the affective and perceptual salience of the pitch of the mothers’ voices indicated that with the younger infants, but not the older infants, both the affective quality and the dynamic range of the mothers’ voices was reduced in the second condition. It is argued that this reduction enables the younger infants to concentrate on the task but restricts access to the linguistic content of what is said. The implications of these findings for intervention programmes are discussed.     

Effects of maternal interference on the attachment and exploratory behavior of one-year-olds

Effects of maternal interference on social behavior toward mother and exploratory play were examined in a laboratory experimental paradigm. Subjects were 40 1-year-olds and their mothers. Mothers of the 20 interference-group infants were instructed periodically to physically interfere with their child's independent object play during the first half of the observation session. A postinterference free-play period immediately followed. The 20 control-group infants were permitted by mother to play freely throughout the session. Groups were matched for exposure to play materials. Despite its aversiveness, interference had no subsequent effect on infant social initiatives to mother, responsiveness to mother's social bids, or exploratory play.