Infant Behavior & Development最新文献

Physical aggression in toddlerhood is empirically linked to anger and often conceptualized as a byproduct of frustration and related negative affect. Further, parenting is the major environmental construct implicated in the development of aggressive behaviors. Given parents’ role as “external regulators,” parents’ responses to their toddlers’ negative affect may serve to escalate or de-escalate their toddlers’ affective experience, thereby impacting the likelihood of subsequent aggression. In the present study, we examined whether parents’ negative affect, harsh, soothing, and distracting responses to their toddlers’ negative affect mediated the relation between toddlers’ negative affect and their aggressive behavior in brief conflict episodes. During a laboratory visit, a community sample of 69 mother-toddler dyads was observed in a structured interaction task. We found that child negative affect is associated with subsequent aggressive behavior by way of maternal harsh responses to negative affect. Negative emotional expression, soothing, and distraction neither facilitated or hindered children’s escalation from negative affect to aggression. Our findings support a dyadic intervention in which patterns of coercive parent-child interactions are targets for prevention and intervention of toddler aggression.

The current study investigates Joint Attention (JA) characteristics (duration, frequency, source of initiation, type of JA, agent of termination, missed and unsuccessful episodes) in preterm and full-term toddlers’ interactions with their mothers and fathers, separately. Thirty-one singleton full-term (Mage = 24.07 months, SD = 1.45; 13 boys) and 17 singleton preterm toddlers (Madjustedage = 24.72 months, SD = 3.39; 12 boys) participated in the study with both parents. JA episodes were examined during dyadic five-minute free play sessions, were coded second-by-second, and were analysed using two-way mixed ANOVAs. Although the total amount of time spent in JA was not significantly different between the preterm and the full-term groups, JA episodes were more frequent, specifically supported JA episodes, and were more often terminated by the child during parent-preterm toddler interactions. Moreover, preterm toddlers missed their fathers’ attempts for JA more often than their mothers’ and more often than full-term toddlers missed their fathers’ and mothers’ bids for JA. Further, regardless of the birth status, toddlers initiated more JA with mothers than fathers, and fathers redirected their child’s attention to initiate JA more than mothers. Findings indicate that preterm toddlers may struggle to respond to JA bids, especially with their fathers, and to sustain their attention on a specific object or event during interactions. Preterm toddlers may need more support to engage in JA relative to their full-term peers, and redirecting attention strategy may not be optimal for them. Also, toddlers’ JA interactions may be different with their mothers and fathers. Findings contribute to the literature by demonstrating preterm toddlers’ JA characteristics with both parents compared to full-term toddlers at age two.

Research has shown that infants’ language development is influenced by their gaze following—an ability linked to their cognitive and social development. Following social learning approaches, this pilot study explored whether variations in gaze following and later vocabulary scores relate to early mother–infant interactions by focusing on the role of mothers’ gaze responsiveness in infants’ attentional and language development. We recruited 15 mother–child pairs in Poland and assessed their engagement in joint attention episodes. Results indicate that mothers foster their infants' gaze-following ability by providing them with numerous opportunities to participate in the task. We also confirmed a correlation between infants’ gaze-following ability at 6 months and their vocabulary scores at 24 months. However, combining both infants’ gaze following and mothers’ gaze monitoring as predictors in one model revealed that maternal gaze monitoring was a stronger predictor of infants’ later vocabulary growth. Overall, this study emphasizes that mothers’ gaze responsiveness is a crucial feature of scaffolding that impacts on infants’ gaze following and language development.

Executive function (EF) is a critical skill for academic achievement. Research on the psychosocial and environmental predictors of EF, particularly among Southeast Asian, agricultural, and low income/rural populations, is limited. Our longitudinal study explored the influence of agricultural environmental, psychosocial, and temperamental factors on children’s emerging EF. Three-hundred and nine farm worker women were recruited during the first trimester of pregnancy. We evaluated the effects of prenatal insecticide exposure and psychosocial factors on “cool” (i.e., cognitive: A-not-B task, looking version) and “hot” EF (i.e., affective, response inhibition) measures of emerging EF. Maternal urine samples were collected monthly during pregnancy, composited, and analyzed for dialkylphosphate (DAP) metabolites of organophosphate insecticides. Psychosocial factors included socioeconomic status, maternal psychological factors, and quality of mother-child behavioral interactions. Backward stepwise regressions evaluated predictors of children’s EF at 12 (N = 288), 18 (N = 277) and 24 (N = 280) months of age. We observed different predictive models for cool EF, as measured by A-not-B task, vs. hot EF, as measured by response inhibition tasks. Report of housing quality as a surrogate for income was a significant predictor of emerging EF. However, these variables had opposite effects for cool vs. hot EF. More financial resources predicted better cool EF performance but poorer hot EF performance. Qualitative findings indicate that homes with fewer resources were in tribal areas where children must remain close to an adult for safety reasons. This finding suggests that challenging physical environments (e.g., an elevated bamboo home with no electricity or running water), may contribute to development of higher levels of response inhibition through parental socialization methods that emphasize compliance. Children who tended to show more arousal and excitability, and joy reactivity as young infants in the laboratory setting had better cognitive performance. In contrast, maternal emotional availability was a significant predictor of hot EF. As expected, increased maternal exposure to pesticides during pregnancy was associated with worse cognitive performance but was not associated with inhibitory control. Identifying risk factors contributing to the differential developmental pathways of cool and hot EF will inform prevention strategies to promote healthy development in this and other unstudied rural, low income Southeast Asian farming communities.

We re-examine whether the type of object played with influences parent-infant joint attention. A within-participants comparison of 24 parent-9-month-old dyads, used head-mounted eye-tracking to measure parental naming and infant attention during play with touchscreen apps on a touchscreen tablet or matched interactive toys. Infants engaged in sustained attention more to the toy than the tablet. Parents named objects less in toy play. Infants exhibited more gaze shifts between the object and their parent during tablet play. Contrasting previous studies, these findings suggest that joint tablet play can be more interactive than with toys, and raise questions about the recommendation that infants should not be exposed at all to such technology.

Introduction

There is substantial diversity within and between contexts globally in caregiving practices and family composition, which may have implications for the early interaction’s infants engage in. We draw on data from the [blinded] project, which longitudinally examined infants in the UK and in rural Gambia, West Africa. In The Gambia, households are commonly characterized by multigenerational, frequently polygamous family structures, which, in part, is reflected in the diversity of caregivers a child spends time with. In this paper, we aim to 1) evaluate and validate the Language Environment Analysis (LENA) for use in the Mandinka speaking families in The Gambia, 2) examine the nature (i.e., prevalence of turn taking) and amount (i.e., adult and child vocalizations) of conversation that infants are exposed to from 12 to 24 months of age and 3) investigate the link between caregiver diversity and child language outcomes, examining the mediating role of contingent turn taking.

Method

We obtained naturalistic seven-hour-long LENA recordings at 12, 18 and 24 months of age from a cohort of N = 204 infants from Mandinka speaking households in The Gambia and N = 61 infants in the UK. We examined developmental changes and site differences in LENA counts of adult word counts (AWC), contingent turn taking (CTT) and child vocalizations (CVC). In the larger and more heterogenous Gambian sample, we also investigated caregiver predictors of turn taking frequency. We hereby examined the number of caregivers present over the recording day and the consistency of caregivers across two subsequent days per age point. We controlled for children’s cognitive development via the Mullen Scales of Early Learning (MSEL).

Results

Our LENA validation showed high internal consistency between the human coders and automated LENA outputs (Cronbach’s alpha’s all >.8). All LENA counts were higher in the UK compared to the Gambian cohort. In The Gambia, controlling for overall neurodevelopment via the MSEL, CTT at 12 and 18 months predicted CVC at 18 and 24 months. Caregiver consistency was associated with CTT counts at 18 and 24 months. The number of caregivers and CTT counts showed an inverted u-shape relationship at 18 and 24 months, with an intermediate number of caregivers being associated with the highest CTT frequencies. Mediation analyses showed a partial mediation by number of caregivers and CTT and 24-month CVC.

Discussion

The LENA provided reliable estimates for the Mandinka language in the home recording context. We showed that turn taking is associated with subsequent child vocalizations and explored contextual caregiving factors contributing to turn taking in the Gambian cohort.

Caregivers use a of combination labeling, pointing, object grasping, and gaze to communicate with infants about referents in their environment. By two years of age, children reliably use these referent-oriented cues to communicate and learn. While there is some evidence from lab-based studies that younger infants attend to and use referent-oriented cues during communication, some more naturalistic studies have found that in the first year of life, infants do not robustly leverage these cues during dyadic interactions. The current study examined parent and infant gaze, touching, pointing, and reaching to referents for a wide range of nouns, verbs, adjectives, and other early-learned words during 59 one-hour head-camera recordings sampled from one English-learning infants’ life between 6 and 12 months of age. We found substantial variability across individual words for all cues. Some variability was explained by referent concreteness and the grammatical category of the label. The parent’s touching of labeled referents increased across months, suggesting that parent-infant-referent interactions may change with development. Future studies should investigate the trajectories of specific types of words and contexts, rather than attempting to discover possibly non-existent universal trajectories of parent and infant referent-oriented behaviors.

Evidence that early parent-child conversation supports early language development suggests a need to understand factors that account for individual differences in parent-child conversation engagement. Whereas most studies focus on demographic factors, we investigated the role of toddler temperament in a longitudinal study of 120 economically strained families. Specifically, we investigated the degree to which toddlers’ negative affectivity and effortful control, considered together as a composite reflecting challenging temperament, accounted for variability in parent-toddler conversation engagement, and whether the frequency of that engagement mediated associations between toddler temperament and toddler expressive language skills. Toddler challenging temperament (i.e., high negative affectivity and low effortful control) and parent-toddler conversation engagement were measured at 18 and 30 months. Toddler expressive language skills were measured at 18, 24, and 36 months. As expected, a path model indicated inverse relations between toddler challenging temperament and concurrent parent-toddler conversation engagement at both 18 and 30 months. Unexpectedly, there were no direct associations between toddler challenging temperament and toddler expressive language skills either concurrently or longitudinally. However, we found indirect effects of toddler challenging temperament on later toddler expressive language skills via parent-toddler conversation engagement. Findings highlight the importance of considering toddler temperamental characteristics in addition to family demographics as important factors that account for variability in parent-toddler conversation engagement.

Index-finger pointing is a milestone in the development of referential communication. Previous research has investigated infants’ pointing with a variety of paradigms ranging from parent reports to field observations to experimental settings, suggesting that lab-based semi-natural interactional settings seem especially suited to elicit and measure infant pointing. With the Covid-pandemic the need for a comparable online tool became evident enabling also efficient, low-cost, large-scale, diverse data collection. The current study introduces a remote online paradigm, based on the established live ‘decorated-room’ paradigm. In Experiment 1, 12-months old infants and their caregivers (N = 24) looked at digitally presented stimuli together while being recorded with their webcam. We coded pointing gestures of infants and caregivers as well as caregivers’ responses to infants’ pointing. In Experiment 2 (N = 47), we optimized stimuli and investigated influences of stimulus characteristics. We systematically varied the style of depiction, stimulus complexity, motion, and facial stimuli. Main findings were that infants and caregivers pointed spontaneously, with mean behaviors ranging within the benchmarks of previously reported findings of the live decorated-room paradigm. Further, the social setting was preserved as revealed by significant relations between parents’ responsive points and infants’ pointing frequency. Analyses of stimuli characteristics revealed that infants pointed more to stimuli depicting faces than to other stimuli. The new remote online paradigm proves a useful addition to established paradigms. It offers novel opportunities for simplified assessments, large-scale sampling, and worldwide, diversified data collection.

The quality of infant-directed speech (IDS) and infant-directed singing (IDSi) are considered vital to children, but empirical studies on protomusical qualities of the IDSi influencing infant development are rare. The current prospective study examines the role of IDSi acoustic features, such as pitch variability, shape and movement, and vocal amplitude vibration, timbre, and resonance, in associating with infant sensorimotor, language, and socioemotional development at six and 18 months. The sample consists of 236 Palestinian mothers from Gaza Strip singing to their six-month-olds a song by their own choice. Maternal IDSi was recorded and analyzed by the OpenSMILE- tool to depict main acoustic features of pitch frequencies, variations, and contours, vocal intensity, resonance formants, and power. The results are based on completed 219 maternal IDSi. Mothers reported about their infants’ sensorimotor, language-vocalization, and socioemotional skills at six months, and psychologists tested these skills by Bayley Scales for Infant Development at 18 months. Results show that maternal IDSi characterized by wide pitch variability and rich and high vocal amplitude and vibration were associated with infants’ optimal sensorimotor, language vocalization, and socioemotional skills at six months, and rich and high vocal amplitude and vibration predicted these optimal developmental skills also at 18 months. High resonance and rhythmicity formants were associated with optimal language and vocalization skills at six months. To conclude, the IDSi is considered important in enhancing newborn and risk infants’ wellbeing, and the current findings argue that favorable acoustic singing qualities are crucial for optimal multidomain development across infancy.