Infant Attention to Dynamic Audiovisual Stimuli: Look Duration From 3 to 9 Months of Age

The goal of this study was to examine developmental change in visual attention to dynamic visual and audiovisual stimuli in 3‐, 6‐, and 9‐month‐old infants. Infant look duration was measured during exposure to dynamic geometric patterns and Sesame Street video clips under three different stimulus modality conditions: unimodal visual, synchronous audiovisual, and asynchronous audiovisual. Infants looked longer toward Sesame Street stimuli than geometric patterns, and infants also looked longer during multimodal audiovisual (synchronous and asynchronous) presentations than during unimodal visual presentations. There was a three‐way interaction of age, stimulus type, and stimulus modality. Significant differences were found within and between age groups related to stimulus modality (visual or audiovisual) while viewing Sesame Street clips. No significant interaction was found between age and stimulus type while infants viewed dynamic geometric patterns. These findings indicate that patterns of developmental change in infant attention vary based on stimulus complexity and modality of presentation.     

Developmental Changes in Visual Scanning of Dynamic Faces and Abstract Stimuli in Infants: A Longitudinal Study

The characteristics of scanning patterns between the ages of 6 and 26 weeks were investigated through repeated assessments of 10 infants. Eye movements were recorded using a corneal‐reflection system while the infants looked at 2 dynamic stimuli: the naturally moving face of their mother and an abstract stimulus. Results indicated that the way infants scanned these stimuli stabilized only after 18 weeks, which is slightly later than the ages reported in the literature on infants' scanning of static stimuli. This effect was especially prominent for the abstract stimulus. From the 14‐week session on, infants adapted their scanning behavior to the stimulus characteristics. When scanning the video of their mother's face, infants directed their gaze at the mouth and eye region most often. Even at the youngest age, there was no indication of an edge effect.     

Gender-Specificity of Women's and Men's Self-Reported Attention to Sexual Stimuli

Men's sexual arousal is largely dependent on the actor's gender in a sexual stimulus (gender-specific), whereas for women, particularly androphilic women, arousal is less dependent on gender (gender-nonspecific). According to information-processing models of sexual response, sexual arousal requires that attention be directed toward sexual cues. We evaluated whether men's and women's self-reported attention to sexual stimuli of men or women were consistent with genital responses and self-reported arousal. We presented gynephilic men (n = 21) and women (n = 22) and androphilic men (n = 16) and women (n = 33) with audiovisual stimuli depicting men or women engaged in sexual activities. Genital responses were continuously recorded and, following each stimulus, participants reported the amount of attention paid to the video and feelings of sexual arousal. Self-reported attention was gender-specific for men and gender-nonspecific for women, and generally mirrored genital responses and self-reported arousal. Gender-specificity of genital responses significantly predicted gender-specificity of self-reported arousal; however, for men only, this effect was significantly mediated by gender-specificity of self-reported attention. Gender differences in gender-specificity of sexual arousal may be partially accounted for by differences in gender-specificity of self-reported attention, although attention may play a greater role in men's sexual arousal than women's.     

Developmental Differences in Infants' Attention to Social and Nonsocial Threats

Research has demonstrated that humans detect threatening stimuli more rapidly than nonthreatening stimuli. Although the literature presumes that biases for threat should be normative, present early in development, evident across multiple forms of threat, and stable across individuals, developmental work in this area is limited. Here, we examine the developmental differences in infants' (4‐ to 24‐month‐olds) attention to social (angry faces) and nonsocial (snakes) threats using a new age‐appropriate dot‐probe task. In Experiment 1, infants' first fixations were more often to snakes than to frogs, and they were faster to fixate probes that appeared in place of snakes vs. frogs. There were no significant age differences, suggesting that a perceptual bias for snakes is present early in life and stable across infancy. In Experiment 2, infants fixated probes more quickly after viewing any trials that contained an angry face compared to trials that contained a happy face. Further, there were age‐related changes in infants' responses to face stimuli, with a general increase in looking time to faces before the probe and an increase in latency to fixate the probe after seeing angry faces. Together, this work suggests that different developmental mechanisms may be responsible for attentional biases for social vs. nonsocial threats.     

Child,Caregiver, and Temperament Contributions to Infant Joint Attention

Little is known about variables that may contribute to individual differences in infant joint attention, or the coordination of visual attention with a social partner. Therefore, this study examined the contributions of caregiver behavior and temperament to infant joint attention development between 9 and 12 months. Data were collected from 57 infants using a caregiver–infant paradigm, an infant–tester paradigm, and a parent report of infant temperament. Nine‐month measures of caregiver scaffolding and infant initiating joint attention (IJA) with testers were significantly related to 12‐month infant IJA with testers. A temperament measure of positive emotional reactivity was related to 9‐month IJA, and a measure of negative emotional reactivity was related to 12‐month IJA. Temperament and caregiver scaffolding measures, however, were not associated with the development of infant responding to joint attention. These results further the understanding of the multiple processes that contribute to joint attention development in infancy, and support the hypothesis that initiating and responding measures tap different aspects of joint attention development.     

Visual Attention to Dynamic Spatial Relations in Infants and Adults

Previous research has found that kinematic features of interactions, such as spatial proximity, capture adult visual attention. The current research uses online measures of gaze behavior to determine attentional capture to objects with reduced interobject spacing in adults as well as infants at 5 and 12 months. The three age groups observed three identical geometrical shapes that moved randomly. Relative distance between the objects was mapped and intervals of high and low spatial proximity were identified. Findings demonstrate that only adults and 12‐month‐olds look significantly more at the objects that are close during instances of high spatial proximity, while 5‐month‐olds look at chance. The findings speak for a developmental trend in oculomotor processes, where a bias to look at objects with high spatial proximity develops within the first year of life.     

Neural Correlates of Individual Differences in Infant Visual Attention and Recognition Memory

Past studies have identified individual differences in infant visual attention based upon peak look duration during initial exposure to a stimulus. Colombo and colleagues found that infants that demonstrate brief visual fixations (i.e., short lookers) during familiarization are more likely to demonstrate evidence of recognition memory during subsequent stimulus exposure than infants that demonstrate long visual fixations (i.e., long lookers). This study utilized event‐related potentials (ERPs) to examine possible neural mechanisms associated with individual differences in visual attention and recognition memory for 6‐ and 7.5‐month‐old infants. Short‐ and long‐looking infants viewed images of familiar and novel objects during ERP testing. There was a stimulus type by looker type interaction at temporal and frontal electrodes on the late slow wave (LSW). Short lookers demonstrated an LSW that was significantly greater in amplitude in response to novel stimulus presentations. No significant differences in LSW amplitude were found based on stimulus type for long lookers. These results indicate deeper processing and recognition memory of the familiar stimulus for short lookers.     

The Infant Orienting With Attention Task: Assessing the Neural Basis of Spatial Attention in Infancy

Infant visual attention develops rapidly over the first year of life, significantly altering the way infants respond to peripheral visual events. Here, we present data from 5‐, 7‐, and 10‐month‐old infants using the Infant Orienting With Attention (IOWA) task, designed to capture developmental changes in visual spatial attention and saccade planning. Results indicate rapid development of spatial attention and visual response competition between 5 and 10 months. We use a dynamic neural field (DNF) model to link behavioral findings to neural population activity, providing a possible mechanistic explanation for observed developmental changes. Together, the behavioral and model simulation results provide new insights into the specific mechanisms that underlie spatial cueing effects, visual competition, and visual interference in infancy.     

Differences in Visual Attention Patterns to Sexually Mature and Immature Stimuli Between Heterosexual Sexual Offenders,Nonsexual Offenders,and Nonoffending Men

Men, whether gynephilic or androphilic, show both early and late attention toward adults and not toward children. We examined early and late visual attention to sexually mature versus immature stimuli in four groups of heterosexual men: sexual offenders against children (SOAC = 18), sexual offenders against adults (SOAA = 16), nonsexual offenders (NSO = 18), and nonoffending men (NOM = 19). We simultaneously presented adult and child stimuli and measured time to first fixation, number of first fixations, total duration of fixation, and fixation count to four areas of interest: entire body, then face, chest, and pelvis. We found a significant interaction where only SOAC tended to fixate more first times to child than to adult stimuli. Conversely, we found longer total duration of fixations for the bodies of adults compared to the bodies of children in all groups; however, in both the total duration of fixations and the fixation count for the whole body, but especially in the chest, SOAC tended to fixate longer and more often on child stimuli than the other two groups of offenders, but not longer or more often than NOM. This study adds to the limited research using eye-tracking techniques in samples of SOAC.     

Maternal Attention‐Directing Strategies and Infant Focused Attention During Problem Solving

Forty‐nine mother‐infant dyads participated in the study. Mothers were observed during free play with their infants to assess their attention‐directing strategies. Infants were observed during the Bayley to assess their focused attention abilities. Assessments were made when infants were 10 and 18 months. Whereas consistently high levels of maintaining over time were modestly associated with better infant focused attention at 18 months, consistently high levels of redirecting were moderately associated with poorer infant focused attention at 18 months. Additionally, more focused attention was associated with higher Bayley scores at both ages. Although the direction of effects could not be determined, the findings suggest links between maternal attention‐directing strategies (maintaining and redirecting) during play and infant attentional abilities during problem solving.     

Developmental Changes and Individual Differences in Trust and Reciprocity in Adolescence

A Trust Game was used to examine trust and reciprocity development in 12–18‐year‐old‐adolescents (N = 496), as findings have been conflicting and transitions in adolescence remain elusive. Furthermore, this study tested the roles of gender, risk, and individual differences in empathy, impulsivity, and antisocial tendencies in trust and reciprocity. Results indicate stability in trust and a decrease in reciprocity across adolescence, but also show that trust and reciprocity choices were influenced by risk, and that empathy mediated the age‐related decrease in reciprocity. Males trusted more than females, but there were no gender differences in reciprocity. These findings highlight the importance of considering individual differences and adolescents’ sensitivities to varying contexts in explaining trust and reciprocity development in adolescence.     

Exploring Infant Gesture and Joint Attention as Related Constructs and as Predictors of Later Language

In infancy, use of gesture and the ability to engage in joint attention with others both predict later language development. Conceptually, gesture and joint attention abilities may reflect a similar underlying social‐communicative skill. However, these abilities are often studied separately. Despite the fact that gesture is often used in episodes of joint attention, little is known about the degree to which measures of gesture use and joint attention ability are associated with one another or how they similarly, or differentially, predict children's language abilities. Participants in this study were 53 infants. At 12 months, multiple measures of infants’ gesture use were gleaned from a free–play interaction with a parent. Infants’ responding to and initiating joint attention were measured via the Early Social‐Communicative Scales (Mundy et al., 2003). Infants’ expressive and receptive language was measured at 24 months with the Mullen Scales of Early Learning (Mullen, 1995). A factor analysis including gesture and joint attention measures indicated that at 12 months, joint attention, particularly responding to joint attention, reflects a similar underlying construct with infant gesture use, yet they uniquely predict later language ability.     

Gender Differences in Facial Reactions to Fear-Relevant Stimuli

The aim of the present study was to explore whether females are specifically more facially reactive than males, or whether females are more emotionally reactive in general, as reflected even by non-facial reactions such as autonomic responding and emotional experience. Forty-eight females and 48 males were exposed to pictures of fear-relevant and fear-irrelevant stimuli while EMG activity was detected from the Corrugator supercilii muscle region. Skin conductance responses (SCRs) were measured, and the participants were also required to rate how unpleasant they experienced the stimuli to be. Fear-relevant stimuli evoked a larger corrugator response than fear-irrelevant stimuli, but only for females. Fear-relevant stimuli also elicited larger SCRs and higher ratings of unpleasantness, but these measures were almost identical for females and males. The present results are consistent with the hypothesis that females are more facially reactive than males, but not more reactive in other respects.     

Developmental Trajectories for Mother–Infant Coregulation in the Second Year of Life

Ten dyads were observed biweekly from 10 to 24 months of infant age while playing together at home with a set of toys. The aim was to examine whether mother–infant coregulation changes over the second year of the infant’s life and whether there are individual differences in that process. Normative trends as well as variability between and within dyads were tested using a multilevel modeling technique. We found that unilateral coregulation, in which only the mother was actively involved in play, largely prevailed at the beginning of the year and then decreased linearly, while symmetrical patterns, implying that the infant was also involved, were for the most part absent at the beginning but then increased rapidly, overtaking unilateral from the middle of the year on and becoming predominant by the end. In particular, symmetrical episodes of shared affect and shared action increased first and then decreased, being replaced by shared language. Variability in data was significant between the dyads, with some dyads advancing toward symmetrical coregulation at an earlier age and more rapidly than the others. It was also significant within the dyads, as the increase in symmetrical coregulation unfolded in a quite irregular manner across the sessions, unlike the decrease in unilateral. Results are discussed with reference to a view of joint attention development as a gradual and complex process.     

Developmental Changes in Infants’ Ability to Cope with Dialect Variation in Word Recognition

Toward the end of their first year of life, infants’ overly specified word representations are thought to give way to more abstract ones, which helps them to better cope with variation not relevant to word identity (e.g., voice and affect). This developmental change may help infants process the ambient language more efficiently, thus enabling rapid gains in vocabulary growth. One particular kind of variability that infants must accommodate is that of dialectal accent, because most children will encounter speakers from different regions and backgrounds. In this study, we explored developmental changes in infants’ ability to recognize words in continuous speech by familiarizing them with words spoken by a speaker of their own region (North Midland‐American English) or a different region (Southern Ontario Canadian English), and testing them with passages spoken by a speaker of the opposite dialectal accent. Our results demonstrate that 12‐ but not 9‐month‐olds readily recognize words in the face of dialectal variation.     

Second‐Order Correlation Learning of Dynamic Stimuli: Evidence from Infants and Computational Modeling

We present two habituation experiments that examined 20‐ and 26‐month‐olds’ ability to engage in second‐order correlation learning for static and dynamic features, whereby learned associations between two pairs of features (e.g., P and Q, P and R) are generalized to the features that were not presented together (e.g., Q and R). We also present results from an associative learning mechanism that was implemented as an autoencoder parallel distributed processing (PDP) network in which second‐order correlation learning is shown to be an emergent property of the dynamics of the network. The experiments and simulation demonstrate that 20‐ and 26‐month‐olds as well as neural networks are capable of second‐order correlation learning in a category context for internal features of dynamic objects. However, the model predicts—and Experiment 3 demonstrates—that 20‐ and 26‐month‐olds are unable to encode second‐order correlations in a noncategory context for dynamic objects with internal features. It is proposed that the ability to learn second‐order correlations represents a powerful but as yet unexplored process for generalization in the first years of life.     

Cross‐Task Stability in Infant Attention: New Perspectives Using the Still‐Face Procedure

Infant visual attention has been studied extensively within cognitive paradigms using measures such as look duration and reaction time, but less work has examined how infant attention operates in social contexts. In addition, little is known about the stability of individual differences in attention across cognitive and social contexts. In this study, a cross‐sectional sample of 50 infants (4 and 6 months of age) were first tested in a look duration and reaction time task with static visual stimuli. Next, their mothers participated with the infants in the still‐face procedure, a mildly distressing social interaction paradigm that involves violation of expectancy. Individual differences in looking and emotion were stable across the phases of the still‐face task. Further, individual differences in looking measures from the visual attention task were related to the pattern of looking shown across the phases of the still‐face procedure. Results indicate that individual differences in attentional measures show moderate stability within cognitive and social contexts, and that the ability of infants to shift and disengage looks may affect their ability to regulate interaction in social contexts.