Growth in emotion understanding across early childhood: A cohort-sequential model of firstborn children across the transition to siblinghood.

Emotion understanding develops rapidly in early childhood. Firstborn children (N = 231, 55% girls/45% boys, 86% White, 5% Black, 3% Asian, 4% Latinx, Mage  = 29.92 months) were recruited into a longitudinal study from 2004 to 2008 in the United States and administered a series of tasks assessing eight components of young children's emotion understanding from ages 1 to 5. Cohort sequential analysis across three cohorts (1-, 2-, and 3-year-olds) demonstrated a progression of children's emotion understanding from basic emotion identification to an understanding of false-belief emotions, even after controlling for children's verbal ability. Emotion understanding scores were related to children's theory of mind and parent reports of empathy, but not emotional reactivity, providing evidence of both convergent and discriminant validity.

Observant, nonaggressive temperament predicts theory of mind development.

Temperament dimensions influence children's approach to and participation in social interactive experiences which reflect and impact children's social understandings. Therefore, temperament differences might substantially impact theory of mind development in early childhood. Using longitudinal data, we report that certain early temperament characteristics (at age 3)--lack of aggressiveness, a shy-withdrawn stance to social interaction, and social-perceptual sensitivity--predict children's more advanced theory-of-mind understanding two years later. The findings contribute to our understanding of how theory of mind develops in the formative preschool period; they may also inform debates as to the evolutionary origins of theory of mind.

Theory of mind and emotion understanding predict moral development in early childhood.

The current study utilized longitudinal data to investigate how theory of mind (ToM) and emotion understanding (EU) concurrently and prospectively predicted young children's moral reasoning and decision making. One hundred twenty-eight children were assessed on measures of ToM and EU at 3.5 and 5.5 years of age. At 5.5 years, children were also assessed on the quality of moral reasoning and decision making they used to negotiate prosocial moral dilemmas, in which the needs of a story protagonist conflict with the needs of another story character. More sophisticated EU predicted greater use of physical- and material-needs reasoning, and a more advanced ToM predicted greater use of psychological-needs reasoning. Most intriguing, ToM and EU jointly predicted greater use of higher-level acceptance-authority reasoning, which is likely a product of children's increasing appreciation for the knowledge held by trusted adults and children's desire to behave in accordance with social expectations.

Infant attention to intentional action predicts preschool theory of mind.

This research examines whether there are continuities between infant social attention and later theory of mind. Forty-five children were studied as infants and then again as 4-year-olds. Measures of infant social attention (decrement of attention during habituation to displays of intentional action) significantly predicted later theory of mind (false-belief understanding). Possibly, this longitudinal association could have been explained by more general developments in IQ, verbal competence, or executive function (rather than continuities in the realm of social cognition). However, the association remained significant and undiminished even when IQ, verbal competence, and executive function were controlled. The findings thus provide strong support for an important continuity in social cognition separable from continuities in more general information processing.

The relationship between temperament style and understanding of human goal-directed action in infants.

The purpose of this research was to investigate the relationship between temperament style and understanding of goal-directed action in 10-11-month-old infants. Infant social understanding was assessed using a looking-time measure similar to Woodward (1998). This method yielded two measures of infant social understanding; 'decrement of attention' (a measure of infant attention during habituation) and 'novelty preference' (an index of infants' understanding of goal-directed behavior). Temperament style was provided by online parent report (IBQ; Rothbart, 1981). Infant shy/fearful temperament predicted decrement of attention scores. Novelty preference was also marginally related to shy temperament, but more strongly associated with low intensity pleasure, specifically enjoyment of physical contact with caregivers. Moreover, shy temperament continued to predict infant social understanding even when controlling for the effect of non-social intelligence (ASQ; Squires, et al., 2009). In our study, as in research with preschool-aged children (Wellman et al., 2011; Mink et al., 2014), shy, reticent temperament style is associated with social information processing, providing further evidence for continuity in individual differences in social cognition in early childhood.

The Social Context of Infant Intention Understanding.

Traditional looking-time paradigms are often used to assess infants' attention to socio-cognitive phenomena, but the link between these laboratory scenarios and real-world interactions is unclear. The current study investigated hypothesized relations between traditional social-cognitive looking-time paradigms and their real-world counterparts in caregiver-infant social interaction. Seventy-five 10- to 12-month-old infants participated in a structured play session with their caregiver, as well as a traditional looking-time paradigm targeting intentional action. Infants' ability to quickly parse intentional displays correlated with several key qualities of their everyday interactions. In particular, caregiver and infant interaction quality, maternal supportiveness, caregiver and infant joint engagement skill, and social attentiveness in infants correlated with faster habituation to looking-time displays. These results support a linkage between social-cognitive looking-time laboratory paradigms and more naturalistic partner interaction, at this key age. The data both provide external validation for the large body of social-cognitive findings emerging from laboratory looking-time paradigms, and contribute to a growing literature tracking the developmental trajectory of infants' understanding of people over the first two years.