Does contingency in adults’ responding influence 12-month-old infants’ social referencing?

In two experiments we examined the influence of contingent versus non-contingent responding on infant social referencing behavior. EXPERIMENT 1: Forty 12-month-old infants were exposed to an ambiguous toy in a social referencing situation. In one condition an unfamiliar adult who in a previous play situation had responded contingently to the infant’s looks gave the infant positive information about the toy. In the other condition an unfamiliar adult who previously had not responded contingently delivered the positive information. EXPERIMENT 2: Forty-eight 12-month-old infants participated in Experiment 2. In this experiment it was examined whether the familiarity of the adult influences infants’ reactions to contingency in responding. In one condition a parent who previously had responded contingently to the infant’s looks provided positive information about the ambiguous toy, and in the other condition a parent who previously had not responded contingently provided the positive information. The infants looked more at the contingent experimenter in Experimenter 1, and also played more with the toy after receiving positive information from the contingent experimenter. No differences in looking at the parent and in playing with the toy were found in Experiment 2. The results indicate that contingency in responding, as well as the familiarity of the adult, influence infants’ social referencing behavior.     

Does contingency in adults’ responding influence 12-month-old infants’ social referencing?

In two experiments we examined the influence of contingent versus non-contingent responding on infant social referencing behavior. EXPERIMENT 1: Forty 12-month-old infants were exposed to an ambiguous toy in a social referencing situation. In one condition an unfamiliar adult who in a previous play situation had responded contingently to the infant’s looks gave the infant positive information about the toy. In the other condition an unfamiliar adult who previously had not responded contingently delivered the positive information. EXPERIMENT 2: Forty-eight 12-month-old infants participated in Experiment 2. In this experiment it was examined whether the familiarity of the adult influences infants’ reactions to contingency in responding. In one condition a parent who previously had responded contingently to the infant’s looks provided positive information about the ambiguous toy, and in the other condition a parent who previously had not responded contingently provided the positive information. The infants looked more at the contingent experimenter in Experimenter 1, and also played more with the toy after receiving positive information from the contingent experimenter. No differences in looking at the parent and in playing with the toy were found in Experiment 2. The results indicate that contingency in responding, as well as the familiarity of the adult, influence infants’ social referencing behavior.     

Social referencing in 10-month-old infants

In Experiment 1, forty 10-month-old infants participated together with an experimenter and a parent in a social referencing encounter. The experimenter or the parent presented an ambiguous toy. Neither of the adults provided information about the toy in order to examine infant spontaneous looking behaviour. The infants looked more at both adults when the experimenter presented the toy. In Experiment 2, forty-four 10-month-old infants participated. The experimenter or the parent provided positive information about an ambiguous toy. The infants played more with the toy when the experimenter provided information than when the parent did. The results are discussed in terms of seeking information from knowledgeable others in ambiguous situations.     

Triadic awareness predicts partner choice in male–infant–male interactions in Barbary macaques

Social knowledge beyond one’s direct relationships is a key in successfully manoeuvring the social world. Individuals gather information on the quality of social relationships between their group companions, which has been termed triadic awareness. Evidence of the use of triadic awareness in natural contexts is limited mainly to conflict management. Here we investigated triadic awareness in wild Barbary macaques (Macaca sylvanus) in the context of bridging interactions defined as male–infant–male interactions whereby a male (initiator, holder) presents an infant to another male (receiver, non-holder) in order to initiate an affiliative interaction with that male. Analyses based on 1263 h of focal observations on ten infants of one wild social group in Morocco supported the hypothesis that males use their knowledge of the relationship between infants and other adult males when choosing a male as a partner for bridging interactions. Specifically, (i) the number of bridging interactions among holder–infant–receiver triads was positively affected by the strength of the infant–receiver relationship and (ii) when two males were available as bridging partners, a male was more likely to be chosen as the receiver the stronger his social relationship with the infant relative to the other available male. This demonstrates that non-human primates establish triadic awareness of temporary infant–male relationships and use it in a naturally occurring affiliative context. Our results contribute to the discussion about the mechanism underlying the acquisition of triadic awareness and the benefits of its usage, and lend support to hypotheses linking social complexity to the evolution of complex cognition.     

Look up to the body: An eye-tracking investigation of 7-months-old infants’ visual exploration of emotional body expressions

The human body is an important source of information to infer a person’s emotional state. Research with adult observers indicate that the posture of the torso, arms and hands provide important perceptual cues for recognising anger, fear and happy expressions. Much less is known about whether infants process body regions differently for different body expressions. To address this issue, we used eye tracking to investigate whether infants’ visual exploration patterns differed when viewing body expressions. Forty-eight 7-months-old infants were randomly presented with static images of adult female bodies expressing anger, fear and happiness, as well as an emotionally-neutral posture. Facial cues to emotional state were removed by masking the faces. We measured the proportion of looking time, proportion and number of fixations, and duration of fixations on the head, upper body and lower body regions for the different expressions. We showed that infants explored the upper body more than the lower body. Importantly, infants at this age fixated differently on different body regions depending on the expression of the body posture. In particular, infants spent a larger proportion of their looking times and had longer fixation durations on the upper body for fear relative to the other expressions. These results extend and replicate the information about infant processing of emotional expressions displayed by human bodies, and they support the hypothesis that infants’ visual exploration of human bodies is driven by the upper body.     

Ontogenetic constraints on neural and behavioral plasticity: evidence from imprinting and face processing.

This paper addresses the extent and limits on brain plasticity during development through the detailed study of imprinting in the domestic chick and the development of face processing in human infants. In both of these systems, evidence for constraints on plasticity is reviewed. The first source of constraint comes from the basic architecture of learning mechanisms that support plasticity. With regard to the chick, a specific "Hebbian" model based on the known neural circuitry of the region of the brain involved is presented and discussed. In human infants, a more abstract model inspired by cortical circuitry is mentioned. The second source of constraint comes from biases on the nature of the stimuli selected for attention by the young organism. Both in the chick and the human there is evidence for a subcortical brain system which orients their attention toward conspecifics, and particularly to their faces. It is argued that these systems tutor, or bias the input to, the more plastic learning systems.     

Demystifying infant vocal imitation: The roles of mouth looking and speaker’s gaze

Vocal imitation plays a fundamental role in human language acquisition from infancy. Little is known, however, about how infants imitate other's sounds. We focused on three factors: (a) whether infants receive information from upright faces, (b) the infant's observation of the speaker's mouth and (c) the speaker directing their gaze towards the infant. We recorded the eye movements of 6‐month‐olds who participated in experiments watching videos of a speaker producing vowel sounds. We found that an infants’ tendency to vocally imitate such videos increased as a function of (a) seeing upright rather than inverted faces, (b) their increased looking towards the speaker's mouth and (c) whether the speaker directed their gaze towards, rather than away from infants. These latter findings are consistent with theories of motor resonance and natural pedagogy respectively. New light has been shed on the cues and underlying mechanisms linking infant speech perception and production.     

Infant pointing serves an interrogative function

In recent years there has been a resurgence of interest in the motivations behind, and the function of, infant pointing behaviour. Many studies have converged on the view that early pointing reflects a motivation to share attention and interest with others. Under one view, it is the sharing of attention itself that is the ultimate function of pointing, and is an early manifestation of a uniquely human social cognition that is geared towards cooperation and collaboration. In the current study, we tested an alternative hypothesis in which the goal of pointing is not attention sharing itself, but the information-laden response that infants tend to receive as a result of sharing attention. If infants indeed point in order to obtain information, their pointing should be modulated by the perceived ability of the other to provide this information. In Experiment 1, 16-month-olds who interacted with a demonstrably knowledgeable experimenter pointed significantly more to novel objects than infants who interacted with an ignorant experimenter. In Experiment 2, we confirmed that this finding was due to the perceived competence of the experimenter rather than to the different ways in which the experimenter responded to infants' points. Our results suggest that one function of pointing in infancy is to obtain information from others, and that infants selectively elicit desired information from those whom they perceive could competently provide it.     

When infants talk,infants listen: pre‐babbling infants prefer listening to speech with infant vocal properties

To learn to produce speech, infants must effectively monitor and assess their own speech output. Yet very little is known about how infants perceive speech produced by an infant, which has higher voice pitch and formant frequencies compared to adult or child speech. Here, we tested whether pre‐babbling infants (at 4–6 months) prefer listening to vowel sounds with infant vocal properties over vowel sounds with adult vocal properties. A listening preference favoring infant vowels may derive from their higher voice pitch, which has been shown to attract infant attention in infant‐directed speech (IDS). In addition, infants' nascent articulatory abilities may induce a bias favoring infant speech given that 4‐ to 6‐month‐olds are beginning to produce vowel sounds. We created infant and adult /i/ (‘ee’) vowels using a production‐based synthesizer that simulates the act of speaking in talkers at different ages and then tested infants across four experiments using a sequential preferential listening task. The findings provide the first evidence that infants preferentially attend to vowel sounds with infant voice pitch and/or formants over vowel sounds with no infant‐like vocal properties, supporting the view that infants' production abilities influence how they process infant speech. The findings with respect to voice pitch also reveal parallels between IDS and infant speech, raising new questions about the role of this speech register in infant development. Research exploring the underpinnings and impact of this perceptual bias can expand our understanding of infant language development.     

4.5-month-old infants’ learning, retention and use of object boundary information

4.5-month-old infants can use information learned from prior experience with objects to help determine the boundaries of objects in a complex visual scene (Needham, 1998; Needham, Dueker, & Lockhead, 2002). The present studies investigate the effect of delay (between prior experience and test) on infant use of such experiential knowledge. Results indicate that infants can use experience with an object to help them to parse a scene containing that object 24 (Experiment 1). Experiment 2 suggests that after 24 h infants have begun to forget some object attributes, and that this forgetting promotes generalization from one similar object to another. After a 72-h delay, infants did not show any beneficial effect of prior experience with one of the objects in the scene (Experiments 3A and B). However, prior experience with multiple objects, similar to an object in the scene, facilitated infant segregation of the scene 72 h later, suggesting that category information remains available in infant memory longer than experience with a single object. The results are discussed in terms of optimal infant benefit from prior experiences with objects.     

Infants' understanding of false labeling events: the referential roles of words and the speakers who use them

The four studies reported here examine whether 16-month-old infants' responses to true and false utterances interact with their knowledge of human agents. In Study 1, infants heard repeated instances either of true or false labeling of common objects; labels came from an active human speaker seated next to the infant. In Study 2, infants experienced the same stimuli and procedure; however, we replaced the human speaker of Study 1 with an audio speaker in the same location. In Study 3, labels came from a hidden audio speaker. In Study 4, a human speaker labeled the objects while facing away from them. In Study 1, infants looked significantly longer to the human agent when she falsely labeled than when she truthfully labeled the objects. Infants did not show a similar pattern of attention for the audio speaker of Study 2, the silent human of Study 3 or the facing-backward speaker of Study 4. In fact, infants who experienced truthful labeling looked significantly longer to the facing-backward labeler of Study 4 than to true labelers of the other three contexts. Additionally, infants were more likely to correct false labels when produced by the human labeler of Study 1 than in any of the other contexts. These findings suggest, first, that infants are developing a critical conception of other human speakers as truthful communicators, and second, that infants understand that human speakers may provide uniquely useful information when a word fails to match its referent. These findings are consistent with the view that infants can recognize differences in knowledge and that such differences can be based on differences in the availability of perceptual experience.     

Perceptual Sensitivity and Motoric Competence in 5- and 6-Month-Old Infants

The authors explored whether 5- to 6-month-old infants were sensitive to perceptual information and how they used perception as a recognition cue to search for a hidden object. In addition, the authors categorized and examined infant grasp by developmental effectiveness to determine any impact on infant search behaviors. In a within-participants design, 20 infants were presented with a toy in 2 occluder conditions. The toy was hidden under either a thick, camouflaging cloth or a thin, semitransparent cloth. The data revealed significant effects of perceptual sensitivity, age, and motor sophistication on search tasks. The results suggest that motor competence might be a limiting factor in infants' abilities to link motoric responses to notions about an object.     

Perceptual sensitivity and motoric competence in 5- and 6-month-old infants

The authors explored whether 5- to 6-month-old infants were sensitive to perceptual information and how they used perception as a recognition cue to search for a hidden object. In addition, the authors categorized and examined infant grasp by developmental effectiveness to determine any impact on infant search behaviors. In a within-participants design, 20 infants were presented with a toy in 2 occluder conditions. The toy was hidden under either a thick, camouflaging cloth or a thin, semitransparent cloth. The data revealed significant effects of perceptual sensitivity, age, and motor sophistication on search tasks. The results suggest that motor competence might be a limiting factor in infants' abilities to link motoric responses to notions about an object.     

Stimulation of premature infants: The boundary between believing and knowing

Over the past two decades, technological and medical advances have resulted in increasing survival and decreasing morbidity for infants who are termed high risk due to prematurity and associated factors. As professionals began to turn their attention toward optimizing the long-term outcome for these infants, a number of pro̧grams collectively known as “infant stimulation” programs were developed. The design and implementation of these programs initially were based on findings from the basic sciences that indicated that environmental enrichment positively affected the immature nervous system, whereas environmental deprivation had adverse effects. Subsequent clinical research that analyzed the effects of stimulation programs for infants in high-risk nurseries has shown beneficial effects of varying types of stimulation on numerous dependent measures. Recently, however, some practitioners have cautioned against viewing these results as conclusive. This article is a review of multi-disciplinary research relevant to infant stimulation programs and includes a critical analysis of research findings and future needs. This analysis leads to the conclusion that many infant stimulation programs have been designed and implemented based on potentially invalid assumptions. Further research is needed prior to establishing what constitutes an optimal infant stimulation program.     

An event-based analysis of the coordination of early infant vocalizations and facial actions

This study used an event-based approach to provide empirical evidence regarding the nature of coordination in 3- and 6-month-old infants. Vocalizations and facial actions of 12 normally developing infants interacting with their caregivers were coded. Coded vocalizations and facial actions were considered coordinated when they temporally overlapped. Results indicate that infants coordinated their vocalizations and facial actions more than expected by chance. Coordinated events were governed by 2 sequence patterns. When 2 communicative events were temporally associated across modalities, 1 event tended to be completely embedded within the other, and vocalizations tended to end before facial actions. This study provides new information about how infant communication is structured, confirms results from other coordination studies, and describes a new method for analysis of event-based data.     

Influences of maternal postpartum depression on fathers and on father–infant interaction

Maternal postpartum depression (PPD) has been shown to negatively influence mother–infant interaction; however, little research has explored how fathers and father–infant interaction are affected when a mother is depressed. This study examined the influence of maternal PPD on fathers and identified maternal and paternal factors associated with father–infant interaction in families with depressed as compared with nondepressed mothers. A convenience sample of 128 mother–father–infant triads, approximately half of which included women with significant symptoms of PPD at screening, were recruited from a screening sample of 790 postpartum women. Mothers and fathers completed measures of depression, marital satisfaction, and parenting stress at 2 to 3 months' postpartum and were each videotaped interacting with their infants. Results indicate that maternal PPD is associated with increased paternal depression and higher paternal parenting stress. Partners of depressed women demonstrated less optimal interaction with their infants, indicating that fathers do not compensate for the negative effects of maternal depression on the child. Although mother–infant interaction did not influence father–infant interaction, how the mother felt about her relationship with the infant did, even more so than maternal depression. The links between maternal PPD, fathers, and father–infant interaction indicate a need for further understanding of the reciprocal influences between mothers, fathers, and infants.     

Infant care from infants' viewpoint: the views of some professionals

Debate about infant care tends to focus on still unresolved questions about whether or not day care is harmful, while research studies often confine care options to an unrealistic axis of choice between group care and mother care. Research that delineates constituents of day care quality in relation to measurable outcomes for different groups of children is urgently needed and should be based on a broader view of infant care options. A postal opinion survey sought the confidential views of members of an international organization of infant mental health professionals as to the kinds of care they considered likely to be best for infants from birth to 36 months, assuming that all types of care were of equally high quality and availability. Surprisingly lengthy periods of care by mothers were consistently endorsed; fathers were almost entirely disregarded as principal or joint caregivers; all forms of family care were endorsed over all forms of purchased care, but all forms of individual care were preferred to full-day group care for all age groups and to half-day group care up to the age of 2. The patterns of care judged by these respondents as likely to be best for infants are very different from those which most infants experience now, and from those which policy- and opinion-makers, practitioners and parents aspire, publicly at least, to provide for infants in the future. ©1997 John Wiley & Sons, Ltd.     

Infants’ sensitivity to familiar size: The effect of memory on spatial perception

Two experiments investigated infants’ sensitivity to familiar size as information for the distances of objects with which they had had only brief experience. Each experiment had two phases: a familiarization phase and a test phase. During the familiarization phase, the infant played with a pair of different-sized objects for 10 min. During the test phase, a pair of objects, identical to those seen in the familiarization phase but now equal in size, were presented to the infant at a fixed distance under monocular or binocular viewing conditions. In the test phase of Experiment 1, 7-month-old infants viewing the objects monocularly showed a significant preference to reach for the object that resembled the smaller object in the familiarization phase. Seven-month-old infants in the binocular viewing condition reached equally to the two test phase objects. These results indicate that, in the monocular condition, the 7-month-olds used knowledge about the objects’ sizes, acquired during the familiarization phase, to perceive distance from the test objects’ visual angles, and that they reached preferentially for the apparently nearer object. The lack of a reaching preference in the binocular condition rules out interpretations of the results not based on the objects’ perceived distances. The results, therefore, indicate that 7-month-old infants can use memory to mediate spatial perception. The implications of this finding for the debate between direct and indirect theories of visual perception are discussed. In the test phase of Experiment 2,5-month-old infants viewing the objects monocularly showed no reaching preference. These infants, therefore, showed no evidence of sensitivity to familiar size as distance information.     

Effects of maternal inattentiveness on infant social referencing

The aim of the study was to clarify the meaning of infant looking behaviour when the infant is confronted with an ambiguous situation in order to disentangle the two processes social referencing and attachment. Ninety‐six 12‐month‐olds, presented with an ambiguous or an unambiguous toy, were assigned to one of four conditions; mother inattentive, mother conveyed positive information, and mother conveyed negative information about the ambiguous toy. In the fourth condition (control condition), an unambiguous toy was presented (mother inattentive). The ambiguous situation elicited more referencing looks than the unambiguous situation. During the presentation of the ambiguous toy, infants with inattentive mothers referenced the experimenter more than infants whose mothers provided guidance. In the following free‐play situation, infants in the inattentive group referenced mother to a higher degree than did the other infants. They played less with the toy than infants who had received positive information and infants in the control group, and were less eager to explore the surroundings than infants in the other three groups. When mother turned attentive the infants ceased referencing her and showed an interest in exploring. Copyright © 2003 John Wiley & Sons, Ltd.