Infancy最新文献

Infants prefer infant-directed (ID) speech. Concerning talking faces, previous research showed that 3- and 5-month-olds prefer faces that produce native ID than native adult-directed (AD) speech, regardless of background speech being ID, AD or silent. Here, we explored whether infants also show a preference for non-native ID speech. We presented 3- and 6-month-old infants with pairs of talking faces, one producing non-native ID speech and the other non-native AD speech, either in silence (Experiment 1) or accompanied by non-native ID or AD background speech (Experiment 2). Results from Experiment 1 showed an overall preference for the silent ID talking faces across both age groups, suggesting a reliance on cross-linguistic, potentially universal cues for this preference. However, Experiment 2 showed that preference for ID faces was disrupted at 3 months when auditory speech was present (ID or AD). At 6 months, infants maintained a preference for ID talking faces, but only when accompanied by ID speech. These findings show that auditory non-native speech interferes with infants' processing of ID talking faces. They also suggest that by 6 months, infants start associating ID features from faces and voices irrespective of language familiarity, suggesting that infants' ID preference may be universal and amodal.

From early in development, infants process faces in their environment differentially from other items. By around 6 months of age, they are able to orient toward faces in the presence of distractor items. This paper aimed to assess whether this preferential looking toward faces was observable prior to 6 months of age, and whether there were developmental trends. We assessed this using the face pop-out task, a free viewing eye-tracking experiment in which infants viewed arrays containing an image of a face, alongside four distractor items. We assessed whether infants at 4, 5, 6 and 7 months (n = 1585 participants) differed in the proportion of first looks, total dwell time, and frequency of fixations to faces compared to other items. All three outcome variables were significantly higher toward faces than toward any of the other items in all the age groups. Moreover, there were age-related differences across all measures—the older the infants were, the more pronounced their face preferences were. These age-related differences could not be attributed to differences in data quality, and thus suggest that face preference is observable at 4 months of age but shows a strong development until 6 months.

Exposure to early life stress shapes further development, affects later stress reactivity, and mental health outcomes. Despite the central role of early experiences, there is little understanding of how these rapidly forgotten events gain their influence. An infant's ability to cope with everyday stressors is founded on successful co-regulation through mother-infant interaction. A significant disruption of this interaction through the Face-to-Face Still-Face paradigm elicits a well-documented behavioral and physiological stress response in infants. What has yet to be explored is whether infants show regulatory adaptions when encountering the situation over again. To fill this gap, 80 mother-infant dyads were observed in the lab on two consecutive days. Infants in the experimental condition (n = 40) were exposed to a double Still-Face paradigm on day one. Infants in the control group (n = 40) completed time-matched episodes of typical play during their first visit. Mother-infant dyads from both groups returned to the lab 24 h later and participated in the double Still-Face paradigm. Changes in behavior (positive and negative affect), physiology (heart rate), and salivary cortisol, compared to day one and between groups, were evaluated and used to infer adaption to the previous experienced laboratory visit. Infants in the experimental condition showed a significant decrease in positive affect (p = 0.016) and an increase in heart rate (p < 0.001) on day two, compared to controls, even during baseline measures and a neutral first play episode. Infants in the control condition showed a significant decrease in affect (p = 0.05) and non-significant increase in heart rate on day two when first encountering the Still-Face paradigm. Infants in the experimental condition showed significant higher heart rate on day two compared to the control group (p = 0.046). Infants in the experimental condition also exhibited a marginally significant increase in salivary cortisol on day two, compared to day one (p = 0.054). The change in infant heart rate was independent of maternal heart rate which did not differ between day one and day two, or between groups. Findings suggest that a previous stressful experience may elicit a behavioral and physiological adaption in infants 24 h later. Our results suggest that even a short, acute stressful event can elicit a lasting stress response in infants 24 h later. The effect we observed was specific to the context of the stressful event, not just the stressor. More precisely, the effect “spilled over” from the stressful experience on day one into the baseline measure of day two, usually a neutral experience. The results could have implications for further research on how stressful experiences may shape the stress response.

Acoustic variability in the speech input has been shown, in certain contexts, to be beneficial during infants' acquisition of sound contrasts. One approach attributes this result to the potential of variability to make the stability of individual cues visible. Another approach suggests that, instead of highlighting individual cues, variability uncovers stable relations between cues that signal a sound contrast. Here, we investigate the relation between Voice Onset Time and the onset of F1 formant frequency, two cues that subserve the voicing contrast in German. First, we verified that German-speaking adults' use of VOT to categorize voiced and voiceless stops is dependent on the value of the F1 onset frequency, in the specific form of a so-called trading relation. Next, we tested whether 6-month-old German learning infants exhibit differential sensitivity to stimulus continua in which the cues varied to an equal extent, but either adhered to the trading relation established in the adult experiment or adhered to a reversed relation. Our results present evidence that infants prefer listening to speech in which phonetic cues conform to certain cue trading relations over cue relations that are reversed.

This study investigated the association between Sensory processing (SP) (i.e., hyporesponsiveness, Sensory Seeking (SS) and hyperresponsiveness) at 10 months (M) and language/social-communicative difficulties at 24M, mediated through object play at 14M in young children at elevated likelihood for autism (EL). Parent-report instruments were used to measure all variables in younger siblings of children with autism (siblings, n = 74) and children born before 30 gestational weeks (preterms, n = 38). Higher scores of object play fully mediated the association between more SS and better language/less social-communicative difficulties. Hypo- and hyperresponsiveness at 10M did not seem to predict language heterogeneity at 24M, but more hypo- and less hyperresponsiveness at 10M were associated with more social-communicative difficulties at 24M. The explained variance in social-communicative difficulties and language was limited (15.25%–16.39%). Similar associations were found for siblings and preterms. This highlights that high frequency of SP behaviors does not necessarily negatively affect communication in young EL-children as is commonly assumed. Early object play skills play a role in the association between early SS and later language/social communicative difficulties. This implies that some criteria of the two core domains of characteristics of autism are interrelated in EL-children, and this may have implications for early intervention programs.

Parent-infant interactions highlight the role of parental input, considering both the quality, infant-directed speech, and quantity of interactions, adult words and communicative turns, in these interactions. However, communication is bidirectional, yet little is known about the infant's role in these interactions. This study (n = 35 4-month-old infants) explores how infant-directed speech, the number of adult words and turn-taking (both measured by the LENA system) are correlated with infants' temperament. Our findings reveal that, while mothers use the typical characteristics of infant-directed speech, they are not correlated with the infant's temperament. However, we observe more adult-infant turn-taking in both introverted infants (with lower Surgency scores) and infants with lower attention regulation (with lower Regulatory/Orienting scores). The number of adult words was not correlated with infants' temperament. We suggest that infants with an introverted temperament prefer quieter exchanges that may lead to more turns and that infants with lower attention regulation might create more opportunities for interactions due to their lower level of self-regulation. These findings suggest that infants' temperament is associated with how adults talk with infants (communicative turns) rather than how adults talk to infants (infant-directed speech, number of adult words). Our results underscore the infant's role in parent-infant communication.

Object play is a ubiquitous context for learning. Existing knowledge on infant object interaction has relied on Euro-American samples and observations confined to laboratory playrooms or families' homes, where object play is typically observed indoors and in rooms brimming with toys. Here we examined infants' everyday object play in Tajikistan, where spaces are uniquely laid out and homes are not child-centered and toy-abundant. The restrictive gahvora cradling practice in Tajikistan may indirectly shape how infants access and engage with objects. We documented how much time infants spent in object play, the types and diversity of objects they contacted, and the locations of play—indoors or outside. We observed 59 infants (12–24 months) during a 45-min naturalistic observation when infants were out of the gahvora. Infants engaged with objects 50% of the time. Despite a lack of object diversity, object interactions were frequent and dispersed throughout observations. Walkers tended to divide their object interactions between time spent indoors and outside, but pre-walkers mostly interacted with objects indoors. Caregivers inadvertently shape infants' opportunities for exploration and play through culturally guided childrearing practices. And infants make due: they take it upon themselves to move, explore, and engage—gleaning culturally relevant routines.

In the current study we identified salient parental factors for child anxiety symptoms by considering the role of stressful life events, maternal anxiety symptoms, maternal depressive symptoms, and maternal neuroticism. Families (N = 399) in an urban area in the United States were participants in a longitudinal study beginning in infancy. Mothers completed measures of stressful life events (Revised Life Events Questionnaire at all visits), maternal anxiety and depressive symptoms (State–Trait Anxiety Inventory and Beck Depression Inventory, respectively, at infancy between 5 and 12 months, at 2 years, and at 3 years), maternal neuroticism (NEO Five–Factor Inventory at infancy), and child anxiety symptoms (Child Behavior Checklist 1.5–5 at 5 years). Linear mixed models (LMMs) were used in analyses. Maternal depressive symptoms from infancy through 3 years were associated with child anxiety symptoms; other main effects modeled (stressful life events, maternal anxiety symptoms, maternal neuroticism) were not associated with child anxiety symptoms. There was a significant interaction effect between stressful life events and maternal depression. Stressful events from infancy through 5 years of age increased risk for child anxiety symptoms at 5 years if the child's mother had a mild mood disturbance or depression, but not for children with non–depressed mothers.

There is robust evidence that infants' gestures and vocalisations and caregivers' contingent responses predict later child vocabulary. Recent studies suggest that dyadic combinations of infants' behaviors and caregivers' responses are more robust predictors of children's vocabularies than these behaviors separately. Previous studies have not yet systematically compared different types of dyadic combinations. This study aimed to compare the predictive value of (a) frequencies of infants' behaviors (vocalisations, points, and shows + gives) regardless of caregivers' responses, (b) frequencies of infants' behaviors that elicited verbal responses, (c) frequencies of infants' behaviors that elicited multimodal responses, and (d) frequencies of infants' behaviors that did not elicit any responses from caregivers. We examined 114 caregiver-infant dyads at 9–11 months and children's concurrent and longitudinal vocabulary outcomes at 2–4 years. We found that infants' points elicited a large proportion of verbal responses from caregivers which were related to children's later receptive vocabularies. We also found that only shows + gives that elicited caregivers' responses related to infants' concurrent gesture repertoires. In contrast, infants' behaviors that did not elicit responses negatively related to child vocabulary. The results highlight the importance of examining dyadic combinations of infants' behaviors and caregivers' responses during interactions when examining relations to children's vocabulary development.

Many in-lab studies have demonstrated that the distribution of word learning moments affects the strength and quality of word representations. How are words distributed in speech to children in their daily lives, and how is distribution related to other input characteristics? The present study analyzes transcripts of language input to English-learning infants from three longitudinal, naturalistic corpora captured between 6 and 39 months of age. To describe how word frequency varies across time, we calculated dispersion scores for all word types for each child. Dispersion quantifies the deviation of observed frequencies in each recording session from expected (uniform across sessions) word frequency, providing a measure of how evenly word utterances were spread across sessions. Dispersion is strongly correlated with frequency and moderately correlated with concreteness across all corpora, such that high frequency and low concreteness words are more evenly dispersed. Correlations with measures of age of acquisition (AoA) varied across corpora, and dispersion did not reliably predict AoA above and beyond frequency and concreteness. The contradiction between the current results and results from in-lab experiments is discussed. This study provides a foundation to explore how word learning unfolds across time and contexts in the real world.