ABSTRACT This study examined how toddlers learn novel words by observing two adults interact in third‐party contexts. Specifically, we examined whether toddlers show stronger evidence of selective referent identification for labeled objects in third‐party contexts and how word learning may be supported by cues of reciprocity between adult interlocutors, including physical exchange of the object, verbal exchange about the object, and/or the adult listener's response to the information provided. Toddlers ( n = 64, Mage = 29.9 mos., SD = 1.7 mos) were assigned to one of four conditions: Object Exchange + Action Imitation, Object Exchange Only, Verbal Exchange + Label Repetition , or Verbal Exchange Only . In the Object Exchange conditions, children observed one adult speaker label and manipulate a target object and then hand it to another adult listener, who either imitated the object manipulation or held the object without manipulation. In the Verbal Exchange conditions, one adult speaker labeled and manipulated the target object without handing it over, and the other adult listener either repeated the label or provided a neutral verbal response. Children's learning was assessed by whether they selected the target object in response to its label; preference responses were used to distinguish target selection from object preference. Children showed stronger evidence of selective referent identification in the Object Exchange conditions compared to the Verbal Exchange conditions. These results suggest that physical exchange of a labeled object between adult interlocutors may help toddlers identify the interaction as referentially relevant and therefore support word learning in third‐party contexts.
ABSTRACT Rudimentary metacognitive skills emerge early in infancy. To date, however, little is known about the developmental course of these early skills or the factors involved in their development. To address this gap, the present study aimed to: (a) map the developmental trajectory of metacognitive uncertainty from 18 to 36 months; (b) examine whether parental metacognitive talk during play predicts this development; and (c) test the relations between these two factors and children's later memory performance. Using a longitudinal design, 60 parent‐child dyads were tested every 6 months using an eye‐tracking cue fixation paradigm to estimate metacognitive uncertainty. The frequency of parental metacognitive talk was collected during a play session shared with their child. Children's memory was assessed at 36 months with a cartoon‐recall task. Growth curve analyses revealed a nonlinear trajectory, with a shift in metacognitive functioning around 24 months that was predicted by parental metacognitive talk. Path analyses indicated that parental talk at 30–36 months and metacognitive accuracy at 24–30 months were both related to children's later memory skills. This study documents early changes in metacognition while highlighting the role of parent‐child interactions in this development.
This study draws on data from the Chilean Longitudinal First Thousand Days Study to examine early caregiving arrangements and their associations with developmental outcomes among 14-month-old children (n = 1161) in Santiago, Chile. We describe the types of care arrangements-parental, grandparental, relatives, center-based, and non-relatives-by main sociodemographic characteristics and explore their relation to infants' daily routines and early development. Results reveal that while most children receive parental care, a notable proportion are cared for by grandparents or attend center-based programs. Controlling for child characteristics, mother and family background, and home environment, children in center-based care exhibited slightly higher cognitive scores (β = 0.69, SE = 0.35, p = 0.047) than those in exclusive parental care. On the other hand, children in non-relatives' care show lower cognitive scores (β = -1.48, SE = 0.70, p = 0.036) than those in parental care. These findings suggest that in contexts like Chile, decisions and possibilities regarding care arrangements are relevant to children, fostering or inhibiting their early development. Implications for policy and practice in early childhood care are discussed.
Although physical aggression emerges in infancy, concurrent with motor development, its possible connection remains poorly understood. Previous research has documented age-related changes in aggression but has not examined how fundamental motor transitions relate to these changes. This investigation examined associations between two key motor milestones (crawling and walking) and aggressive behavior patterns in early childhood. Mothers (N = 377) of infants aged 4-15 months reported on their children's locomotor abilities, aggressive behaviors (directed and exploratory), defiance, and temper loss. Results showed distinct developmental trajectories for different forms of aggression. The prevalence of directed aggression (e.g., hitting, kicking) increased linearly with age, and exploratory aggression (e.g., biting, hair-pulling) followed a curvilinear pattern, plateauing around 9 months of age before declining. Frequency patterns also differed. Exploratory aggression frequency declined linearly with age and directed aggression frequency decreased initially before trending upward around 11 months. The transition to independent walking, but not crawling, was associated with increased frequency of both types of aggression. These effects were mediated through increases in both defiance and temper loss; the indirect effect through temper loss was significantly stronger for directed than exploratory aggression in single-mediator models. These findings suggest that the transition to walking may serve as a reorganizing force in early aggressive behavior in infancy by influencing emerging behavioral opposition and negative emotional expression. Results contribute to a small but growing literature on the developmental systems that underlie aggression in infancy.
Musical engagement is a universal trait of human behavior and a foundational form of embodied communication. While this engagement is deeply rooted in bodily experiences, much of the existing research has focused on perceptual and neural mechanisms, with comparatively little attention paid to how the body's physical affordances, including the differing biomechanical properties of distinct effectors, shape early rhythmic engagement with music. The current study aims to characterize how rhythmic motoric responses to music vary in the context of an infant's developing physical skills and attributes. Pre-ambulatory infants were placed in an unweighting paradigm to vary levels of postural support as duration and rate of rhythmic movement were measured across core and distal effectors. Results indicated that greater postural support resulted in increased durations and quicker rates of rhythmic movement and enabled qualities of bounce and rebound within infants' movement repertoire, an effect driven primarily by core effectors. Rate of rhythmic movement was found to be organized primarily by effector type, with core movements consistently slower than distal movements across all conditions. Distinct trends between core and distal effectors were found, with vertically displaced core movements consistently slower in rate and increased in duration with age, while distal movements were faster in rate and showed no significant change in duration with age. These patterns align with principles of biomechanics and mass distribution, reflecting a hierarchical organization of rhythmic movement across the body that parallels patterns observed in adults. Findings suggest that postural support facilitates the emergence of more fully embodied musical engagement, offering insight into the sensorimotor foundations of early rhythmic movement.
