Infancy最新文献

Children learn from others by imitating observed behavior. According to some theorists, to imitate an agent's action, infants need to identify the agent's action goal. To test this assumption, goal-predictive gaze shifts of 104 German 12-month-olds (57 female) were measured using live eye-tracking. These goal-predictive gaze shifts were related to their imitation of an action performed by a live model. This relationship was controlled for in terms of cognitive developmental status. We used one task of the imitation battery FIT 12 and analyzed the infants' imitation and goal-predictive gaze shifts. The infants showed goal-predictive gaze shifts to actions presented at a realistic speed. Furthermore, imitation was related to their goal-predictive gaze shifts. This association was partially explained by cognitive-developmental status, which should be considered an important factor in the development of imitation.

Interactions with caregivers play a crucial role in early development. While most of the world's children live in Majority World countries, research on caregiving predominantly uses measures developed in the Minority World (particularly North America and Europe), potentially biasing characterizations of parenting in understudied populations. This study describes the development of the “Demba Yaal Interaction Scale (DYIS)”, a behavioral micro-coding scheme to assesses caregiver responsiveness in a rural, low-resource, collectivist caregiving community in The Gambia. We adopted a contextually sensitive approach by co-creating the scheme partnering Gambian researchers, familiar with the caregiving context, and UK researchers familiar with behavioral coding. The scheme was piloted on 5-min videorecorded mother-infant interactions, when infants were aged 12-months (N = 50, 48% female). There were substantial individual differences in maternal responsiveness levels. Modality-wise, responses were most likely to be non-verbal, compared to verbal or bimodal. Mothers with some formal education were significantly more responsive and more readily engaged in bimodal responsiveness. Negative associations between these interactive behaviors and maternal demographic and socioeconomic variables (age, number of children, household size) were present but did not remain significant after correction for multiple comparisons. Moreover, associations emerged between infant physical growth and infant behaviors, as well as between maternal responsiveness and infant communication, although these too, did not remain significant after correction for multiple comparison. Our work provides a potential framework for future research seeking to develop contextually tailored assessments of caregiving practices and highlights important demographic and health variables that warrant further examination in larger samples.

Post-encoding sleep facilitates memory consolidation from early infancy. Learning from digital content might also benefit from post-encoding sleep. However, infants find it more difficult to learn and remember screen content (transfer deficit) and may only recognize its relevance when scaffolded by caregivers. We investigated infants' memory performance as a function of presentation mode (live or video), post-encoding sleep, and caregiver scaffolding with the aim of replicating the transfer deficit and the beneficial effect of a post-encoding nap. We expected the nap benefit to be less pronounced when information was encoded from videos. We compared data from a live (n = 68) and a video experiment (n = 69). In both experiments, 15- and 24-month-olds watched demonstrations of two deferred imitation tasks (live or on prerecorded video). During one of the demonstrations, caregivers scaffolded the task. Half of the infants in each age-group napped for ≥ 30 min after demonstration, whereas the others remained awake for ≥ 4 h. Memory performance was assessed after 24 h counting the reproduced target actions. Contrary to expectations, the nap benefit did not replicate in the live demonstration sample. However, when both samples were examined together there was a main effect of nap condition showing that infants who had napped retrieved more target actions than awake infants. Moreover, cross-experiment comparisons revealed a transfer deficit and an unexpected disruptive effect of caregiver scaffolding on memory performance in 15-month-olds. Results are discussed in light of limits on detecting sleep-mediated memory effects and the challenges of remembering digital information in infancy due to cognitive load.

Previous research has shown that infants' abilities to sustain attention are influenced by caregivers' attentional behaviors. Here, we inquired whether brain function in infants was linked to brain function in caregivers during attention periods in dyadic interactions, and whether this brain function was associated with visual short-term memory in infants. Caregivers (n = 90, mean age = 33.5 years) and infants (n = 91, mean age = 251.3 days) were recorded for 5- to 7-min as they naturalistically played with toys. During these interactions, brain function was recorded using functional near-infrared spectroscopy (fNIRS). To assess visual short-term memory, infants were presented with a preferential looking task. Video recordings were coded for periods of joint attention between caregivers and infants, and periods of continued attention in infants. fNIRS data was processed to extract significant clusters of activation. Our findings revealed that temporo-parietal engagement in both caregivers and infants. Specifically, left superior temporal gyrus activation in caregivers during joint attention was linked to duration of joint attention, duration of continued attention, and visual short-term memory in infants. Our findings highlight cortical mechanisms engaged in caregivers and infants during dyadic interactions, and importantly, how these mechanisms are linked to visual short-term memory.

To investigate the development of positive affect during early infancy across cultures, we conducted a joyful affect–eliciting dyadic face-to-face interaction between a female experimenter and 3- and 4.5-month-old infants from Münster (urban Germany; n = 20 at 3 months, n = 20 at 4.5 months) and indigenous Kichwa families from the Andean context (rural Ecuador; n = 24 at 3 months, n = 27 at 4.5 months), which differ in their ethnotheories about infants' ideal affect. Results pointed to cross-cultural differences in infants' affective reactivity to high-intensity stimulation, namely higher intensities of positive affect at 3 months in Münster as compared to Kichwa infants that disappeared at 4.5 months of age. The findings serve as an important complement to naturalistic studies that have left open the question of the developmental continuity of cross-cultural differences in infant positive affect beyond 3 months. We discuss our findings in terms of a dynamic interaction between culturally informed parent-infant interactions and biological potentials that give rise to both cross-cultural similarities and differences in the course of emotional development, even in early infancy.

To learn a word from an everyday context, infants need to be able to link the heard word with the correct object perceived. A prevailing view of the early learning environment is that infants' world is bombarded with objects and words. Therefore, it is difficult to find the named object from many possible candidates. However, building correct word-referent mappings relies on in-moment visual selection, it is not clear what infants attend to when learning words in a naturalistic context. Toward this goal, we conducted an eye-tracking experiment in which 12-month-old infants were presented with complex visual scenes extracted from infants' egocentric videos recorded during naturalistic parent-child toy play. These scenes were selected at naming moments when parents labeled a toy object during free-flowing play. We selected visual scenes from a mix of more or less ambiguous naming events that contained different visual properties of the named objects and measured infants' real-time object-looking behaviors. We found that, despite the different visual properties of infants' egocentric scenes, early visual attention is both selective and variable. Selective visual attention is highly constrained by the visual saliency of the learning scenes, but not influenced by labels or existing word knowledge. Infants are more likely to attend to the named object when it is salient in the egocentric view. Our results suggest that although infants' naturalistic learning environment appears to be messy in terms of the number of possible objects for a heard object name, their selective attention significantly reduces the in-moment uncertainty associated with object name learning.