Infant Smiling Dynamics and Perceived Positive Emotion

To better understand early positive emotional expression, automated software measurements of facial action were supplemented with anatomically based manual coding. These convergent measurements were used to describe the dynamics of infant smiling and predict perceived positive emotional intensity. Over the course of infant smiles, degree of smile strength varied with degree of eye constriction (cheek raising, the Duchenne marker), which varied with degree of mouth opening. In a series of three rating studies, automated measurements of smile strength and mouth opening predicted naïve (undergraduate) observers’ continuous ratings of video clips of smile sequences, as well as naïve and experienced (parent) ratings of positive emotion in still images from the sequences. An a priori measure of smile intensity combining anatomically based manual coding of both smile strength and mouth opening predicted positive emotion ratings of the still images. The findings indicate the potential of automated and fine-grained manual measurements of facial actions to describe the course of emotional expressions over time and to predict perceptions of emotional intensity.     

Adult Perceptions of Positive and Negative Infant Emotional Expressions

Adults' perceptions provide information about the emotional meaning of infant facial expressions. This study asks whether similar facial movements influence adult perceptions of emotional intensity in both infant positive (smile) and negative (cry face) facial expressions. Ninety‐five college students rated a series of naturally occurring and digitally edited images of infant facial expressions. Naturally occurring smiles and cry faces involving the co‐occurrence of greater lip movement, mouth opening, and eye constriction, were rated as expressing stronger positive and negative emotion, respectively, than expressions without these 3 features. Ratings of digitally edited expressions indicated that eye constriction contributed to higher ratings of positive emotion in smiles (i.e., in Duchenne smiles) and greater eye constriction contributed to higher ratings of negative emotion in cry faces. Stronger mouth opening contributed to higher ratings of arousal in both smiles and cry faces. These findings indicate a set of similar facial movements are linked to perceptions of greater emotional intensity, whether the movements occur in positive or negative infant emotional expressions. This proposal is discussed with reference to discrete, componential, and dynamic systems theories of emotion.     

Automated measurement of infant and mother Duchenne facial expressions in the Face-to-Face/Still-Face

Although still-face effects are well-studied, little is known about the degree to which the Face-to-Face/Still-Face (FFSF) is associated with the production of intense affective displays. Duchenne smiling expresses more intense positive affect than non-Duchenne smiling, while Duchenne cry-faces express more intense negative affect than non-Duchenne cry-faces. Forty 4-month-old infants and their mothers completed the FFSF, and key affect-indexing facial Action Units (AUs) were coded by expert Facial Action Coding System coders for the first 30 s of each FFSF episode. Computer vision software, automated facial affect recognition (AFAR), identified AUs for the entire 2-min episodes. Expert coding and AFAR produced similar infant and mother Duchenne and non-Duchenne FFSF effects, highlighting the convergent validity of automated measurement. Substantive AFAR analyses indicated that both infant Duchenne and non-Duchenne smiling declined from the FF to the SF, but only Duchenne smiling increased from the SF to the RE. In similar fashion, the magnitude of mother Duchenne smiling changes over the FFSF were 2–4 times greater than non-Duchenne smiling changes. Duchenne expressions appear to be a sensitive index of intense infant and mother affective valence that are accessible to automated measurement and may be a target for future FFSF research.     

The quantification of smiling using a microcomputer-based approach

This study examines the relationship between the ratings made of a set of smiling and neutral expressions and the facial features which influence these ratings. Judges were shown forty real face photographs of smile and neutral expressions and forty line drawings derived from these photographs and were asked to rate the degree of smiling behavior of each expression. The line drawings of the face were generated by a microcomputer which utilizes a mathematical model to quantify facial expression. Twelve facial measures were generated by the computer. Significant differences were found between the ratings of smile and neutral expressions. The Mode of Presentation did not contribute significantly to the ratings. Using the facial measures as separate covariates, five mouth measures and one eye measure were found to discriminate significantly between the ratings made on smile and neutral expressions. When entered as simultaneous covariates, only four mouth measures contributed to the differences found in the expression ratings. Future research projects which may utilise the computer model are discussedThe research reported in this paper was conducted in the Department of Psychology, University of Adelaide. The authors would like to thank Ulana Sudomlak for her assistance in the gathering and recording of the data for this project, and the reviewers for their helpful comments on an earlier version of this paper.     

Maternal Into‐The‐Face Behavior,Shared Attention,and Infant Distress During Face‐to‐Face Play at 12 Months: Bi‐directional Contingencies

We describe a new maternal intrusion behavior, moving a toy or hand “into‐the‐face” of the infant, and we investigate its bi‐directional associations with infant‐initiated shared attention, infant distress, and infant gaze, during mother–infant face‐to‐face play at 12 months. The play was videotaped split‐screen, with infants seated in a high chair. Videotapes were coded on a 1‐sec time base for mother and infant gaze (at partner, toy, both, or gaze away); infant distress; and maternal intrusion behavior, “into‐the‐face.” We defined “infant‐initiated shared attention” as mother and infant looking in the same second at a toy that the infant‐initiated interest in. We documented that maternal into‐the‐face behavior decreased the likelihood of infant‐initiated shared attention, increased the likelihood of infant distress, and decreased the likelihood of infant gazing away. Reciprocally, infant distress and gazing away increased the likelihood of mother into‐the‐face. In moments when the dyad was engaged in infant‐initiated shared attention, mother into‐the‐face was less likely. This work documents bi‐directional contingencies in the regulation of maternal intrusion and infant behavior during face‐to‐face play at 12 months. We suggest that mother into‐the‐face behavior disturbs an aspect of the infant's experience of recognition.     

Categorical Representation of Facial Expressions in the Infant Brain

Categorical perception, demonstrated as reduced discrimination of within‐category relative to between‐category differences in stimuli, has been found in a variety of perceptual domains in adults. To examine the development of categorical perception in the domain of facial expression processing, we used behavioral and event‐related potential (ERP) methods to assess discrimination of within‐category (happy‐happy) and between‐category (happy‐sad) differences in facial expressions in 7‐month‐old infants. Data from a visual paired‐comparison test and recordings of attention‐sensitive ERPs showed no discrimination of facial expressions in the within‐category condition, whereas reliable discrimination was observed in the between‐category condition. The results also showed that face‐sensitive ERPs over occipital‐temporal scalp (P400) were attenuated in the within‐category condition relative to the between‐category condition, suggesting a potential neural basis for the reduced within‐category sensitivity. Together, these results suggest that the neural systems underlying categorical representation of facial expressions emerge during the early stages of postnatal development, before acquisition of language.     

Eye‐Tracking as a Measure of Responsiveness to Joint Attention in Infants at Risk for Autism

Reduced responsiveness to joint attention (RJA), as assessed by the Early Social Communication Scales (ESCS), is predictive of both subsequent language difficulties and autism diagnosis. Eye‐tracking measurement of RJA is a promising prognostic tool because it is highly precise and standardized. However, the construct validity of eye‐tracking assessments of RJA has not been established. By comparing RJA an eye‐tracking paradigm to responsiveness to joint attention during the ESCS, the current study evaluated the construct validity of an eye‐tracking assessment of RJA for 18‐month‐old infant siblings of children with autism. Relations between measures of RJA and concurrent language skills and autistic symptomatology were assessed. Correlations between measures of ESCS RJA and eye‐tracking RJA were statistically significant, but few relations between either ESCS or eye‐tracking assessments of RJA and language or symptoms were observed. This study establishes the construct validity of eye‐tracking assessments of RJA.     

Urgent engagement in 9/11 pregnant widows and their infants: Transmission of trauma

The potential effects of maternal trauma on mother–infant interaction remain insufficiently studied empirically. This study examined the effects of the September 11, 2001, trauma on mother–infant interaction in mothers who were pregnant and widowed on 9/11, and their infants aged 4–6 months. Split‐screen videotaped interaction was coded on a one‐second basis for infant gaze, facial affect, and vocal affect; and mother gaze, facial affect, and touch. We examined the temporal dynamics of communication: self‐contingency and interactive contingency of behavior by time‐series methods. We documented heightened maternal and infant efforts at engagement in the 9/11 (vs. control) dyads. Both partners had difficulty tolerating moments of looking away as well as moments of negative behavior patterns. Heightened efforts to maintain a positive visual engagement may be adaptive and a potential source of resilience, but these patterns may also carry risk: working too hard to make it work. A vigilant, hyper‐contingent, high‐arousal engagement was the central mode of the interpersonal transmission of the trauma to these infants, with implications for intervention.     

Relation Between Maternal Contingent Responsiveness and Infant Social Expectations

This study investigated the relation between maternal contingent responsiveness and 4‐ and 5‐month‐old infants' (N = 64) social expectation behavior in a still‐face procedure. Mothers were asked to interact with their infants for 2 min (interactive phase), remain still‐faced for 1 min (still‐face phase), and resume interaction for 2 min. Mother and infant behavior was assessed for the frequency of infant and mother smiles, mother smiles that were contingent to infant smiles and infant smiles were contingent to mother smiles during the interactive phase, and infant social bids to mother during the still‐face phase. Hierarchical regression showed that mother contingent smiles during the interactive phase accounted for unique variance in infant social bids during the still‐face phase beyond that accounted for by the frequency of mother and infant smiles during the interactive phase. These results support the view that young infants' social expectations and sense of self‐efficacy are formed within their interactions with their caregivers.     

Developmental Trajectories of Emotion Regulation Across Infancy: Do Age and the Social Partner Influence Temporal Patterns

The ability to effectively regulate emotions is a critical component of early socio‐emotional development. This longitudinal study examined the developmental trajectories of emotion regulation in a sample of 3‐, 5‐, and 7‐month‐olds during an interaction with mothers and fathers. Infants' negative affect and use of behavioral strategies, including distraction, self‐soothing, and high intensity motor behaviors were rated during the still‐face episode of the Still‐Face Paradigm. Longitudinal mixed‐effects models were tested to determine whether strategies were followed by an increase or decrease in negative affect. Results from mother‐infant and father‐infant dyads indicated that focusing attention away from the unresponsive parent and engaging in self‐soothing behaviors were associated with a subsequent decline in negative affect and the strength of these temporal associations were stable across infancy. In contrast, high‐intensity motor behaviors were followed by an increase in negative affect and this effect declined over time. No significant effects were found for the behavioral strategy of looking at the parent. Results underscore the importance of considering infant age and the social partner when studying the effectiveness of emotion regulatory strategies in early infancy.     

Relationship Between Maternal Sensitivity During Early Interaction and Maternal Ability in Perceiving Infants' Body and Face

Maternal sensitivity has been considered an indicator of mother‐infant quality interaction, however little is known about the perception processes associated to this parental behavior style. Here we aimed to explore the relationship between maternal sensitivity during a face‐to‐face interaction with their infants and maternal ability in perceiving infants' body and face. Thirty‐six 6 month‐old infants and their mothers were videotaped during a mother‐infant interaction to identify those with high and low sensitivity. Then, mothers were tested using an inversion effect paradigm requiring the visual discrimination of upright and inverted pictures of whole bodies and faces of their own and unfamiliar infants; this allowed estimation of their configural perceptual processing abilities. Results showed that high‐sensitivity mothers showed reduced body configural processing for others' infants as compared to configural processing of their own infant, whereas low‐sensitivity mothers were engaged in comparable body configural processing independently from infant identity. Infants' face configural processing did not distinguish between high‐ and low‐sensitivity mothers. Our findings suggest that high‐sensitivity mothers have refined their use of configural processing of body postures to be selective for their own infants, suggesting that this visuo‐perceptual strategy makes much more efficient the mothers' ability in detecting, discriminating and recognizing own infant's cues.     

Infants of Depressed Mothers Show Reduced Gaze Activity During Mother–Infant Interaction at 4 Months

Gaze is one of the main means of communication in young infants, and it has been shown to be important for subsequent socio‐emotional and cognitive development. Maternal depression is a well‐known risk factor for disrupting mother–infant interactions, but findings regarding gaze behavior in infants of depressed versus nondepressed mothers have been ambiguous. In this study, we examined gaze duration and activity in a sample of 27 infants of mothers with postpartum depression (PPD) and 49 infants of nondepressed mothers. Maternal depressive symptoms were assessed with the Edinburgh Postnatal Depression Scale, and diagnoses were confirmed in clinical interview. Infant gaze was assessed during 4‐month face‐to‐face interactions using continuous timed‐event coding with high temporal resolution. Although we found no differences in gaze duration, infants of PPD mothers had both significantly less Gaze On and also less Gaze Off events. Findings suggest that PPD is related to reduced gaze activity during mother–infant interaction in 4‐month‐olds. This reduced activity may have long‐term negative consequences for child development.     

Greater Pupil Size in Response to Emotional Faces as an Early Marker of Social‐Communicative Difficulties in Infants at High Risk for Autism

When scanning faces, individuals with autism spectrum disorder (ASD) have shown reduced visual attention (e.g., less time on eyes) and atypical autonomic responses (e.g., heightened arousal). To understand how these differences might explain subclinical variability in social functioning, 9‐month‐olds, with or without a family history of ASD, viewed emotionally expressive faces, and gaze and pupil diameter (a measure of autonomic activation) were recorded using eye‐tracking. Infants at high risk for ASD with no subsequent clinical diagnosis (HRA‐) and low‐risk controls (LRC) showed similar face scanning and attention to eyes and mouth; attention was overall greater to eyes than mouth, but this varied as a function of the emotion presented. As a group, HRA‐ showed significantly larger pupil size than LRC. Correlations between scanning at 9 months, pupil size at 9 months, and 18‐month social‐communicative behavior, revealed positive associations between pupil size and attention to both face and eyes at 9 months in LRC, and a negative association between 9‐month pupil size and 18‐month social‐communicative behavior in HRA‐.The present findings point to heightened autonomic arousal in HRA‐. Further, with greater arousal relating to worse social‐communicative functioning at 18 months, this work points to a mechanism by which unaffected siblings might develop atypical social behavior.     

A New Perspective on Neonatal Smiling: Differences Between the Judgments of Expert Coders and Naive Observers

To better understand the form and recognizability of neonatal smiling, 32 newborns (14 girls; M = 25.6 hr) were videorecorded in the behavioral states of alertness, drowsiness, active sleep, and quiet sleep. Baby Facial Action Coding System coding of both lip corner raising (simple or non‐Duchenne) and lip corner raising with cheek raising (Duchenne smile) was followed by a smile recognition task using 48 naive observers. Both types of smiles were detected in all behavioral states. Lip corner raising with cheek raising (Duchenne smiling) tended to predominate in active (rapid eye movement) sleep, suggesting a potential tie to early constituents of emotion. A significant portion of the typically briefer lip corner raising distinguished by expert coders was not recognized as smiling by the naive observers. These briefer actions may represent a motor phenomenon idiosyncratic to the neonatal period.     

Young Infants Match Facial and Vocal Emotional Expressions of Other Infants

Research has demonstrated that infants recognize emotional expressions of adults in the first half year of life. We extended this research to a new domain, infant perception of the expressions of other infants. In an intermodal matching procedure, 3.5‐ and 5‐month‐old infants heard a series of infant vocal expressions (positive and negative affect) along with side‐by‐side dynamic videos in which one infant conveyed positive facial affect and another infant conveyed negative facial affect. Results demonstrated that 5‐month‐olds matched the vocal expressions with the affectively congruent facial expressions, whereas 3.5‐month‐olds showed no evidence of matching. These findings indicate that by 5 months of age, infants detect, discriminate, and match the facial and vocal affective displays of other infants. Further, because the facial and vocal expressions were portrayed by different infants and shared no face–voice synchrony, temporal, or intensity patterning, matching was likely based on detection of a more general affective valence common to the face and voice.     

Additional Components of the Still‐Face Effect: Commentary on Adamson and Frick

Adamson and Frick (2003/this issue) provide an informative and often fascinating history of the still‐face paradigm and its applications in infancy research. With benefit of their review, one can identify several potentially important components of the still‐face paradigm that have been neglected in past research. These are the influence of the still face on parent and infant behavior during the reunion episode and expanded measurement of the still‐face effect to include theoretically important components of facial expression and the temporal organization of parent and infant behavior and physiology. In particular, by expanding what is meant by the still‐face effect to encompass aspects of the reunion episode, we may discover robust probes into the parent–infant relationship and individual differences in infant attachment and emotion regulation extending across infancy and childhood.     

Four‐Month Attentional Regulation and Its Prediction of Three‐Year Compliance

The extent to which 4‐month attentional regulation during an infant‐mother still‐face situation and 12‐month attachment security during the Strange Situation predicted rates of compliance and noncompliance during a cleanup task at 36 months was examined longitudinally in 70 infant‐mother dyads. Hierarchical multiple regression analyses indicated that infants who showed more attentional regulation during the still‐face situation with mothers later showed a higher rate of committed compliance and a lower rate of situational compliance during cleanup with mothers. Furthermore, lower levels of attentional regulation were later associated with higher rates of assertive behavior, but only for infants in an insecure attachment relationship.     

What drives the attentional bias for fearful faces? An eye‐tracking investigation of 7‐month‐old infants’ visual scanning patterns

Seven‐month‐old infants display a robust attentional bias for fearful faces; however, the mechanisms driving this bias remain unclear. The objective of the current study was to replicate the attentional bias for fearful faces and to investigate how infants’ online scanning patterns relate to this preference. Infants’ visual scanning patterns toward fearful and happy faces were captured using eye tracking in a paired‐preference task, specifically exploring if the fear preference is driven by increased attention to particular facial features. Infants allocated increased attention toward the fearful face compared to the happy face overall, thus successfully replicating the attentional bias, and greater attention toward the fearful eyes was associated with a greater magnitude of the fear preference. The current findings suggest that the fearful eyes are a salient facial feature in capturing infants’ attention toward the fearful face and that increased scanning of the fearful eyes may be one mechanism driving the overall fear preference. In addition, scanning patterns, and attention to critical features specifically, are highlighted as a strategy for examining the mechanisms underlying the development of emotion recognition abilities in infancy.     

Associations of Low‐Income Working Mothers' Daily Interactions With Supervisors and Mother‐Child Interactions

This study investigated associations of low‐income working mothers' daily interactions with supervisors and their interactions with children. Sixty‐one mothers of preschool‐aged children were asked to report on their interactions with their supervisors at work and their interactions with children for 2 weeks (N = 520 workdays). Results show significant within‐day spillover from the quality of mothers' perceived work interactions with supervisors to their reports of interactions with children. Supervisor criticism was positively correlated with harsh and withdrawn mother–child interactions on the same day. Supervisor recognition for good work was positively associated with warm mother–child interactions on the same day. Lagged analyses showed some significant associations between perceived supervisor interactions on a given day and mother–child interactions the next day.     

Newborns' Face Recognition: The Role of Facial Movement

This study investigates the role of dynamic information in identity face recognition at birth. More specifically we tested whether semi‐rigid motion, conveyed by a change in facial expression, facilitates identity recognition. In Experiment 1, two‐day‐old newborns, habituated to a static happy or fearful face (static condition) have been tested using a pair of novel and familiar identity static faces with a neutral expression. Results indicated that newborns manifest a preference for the familiar stimulus, independently of the facial expression. In contrast, in Experiment 2 newborns habituated to a semi‐rigid moving face (dynamic condition) manifest a preference for the novel face, independently of the facial expression. In Experiment 3, a multistatic image of a happy face with different degrees of intensity was utilized to test the role of different amount of static pictorial information in identity recognition (multistatic image condition). Results indicated that newborns were not able to recognize the face to which they have been familiarized. Overall, results clearly demonstrate that newborns' face recognition is strictly dependent on the learning conditions and that the semi‐rigid motion conveyed by facial expressions facilitates identity recognition since birth.