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The current study examines if 12-month-old infants and adults perceptions of apparent motion stimuli are context dependent by measuring sensitivity to possible and impossible apparent motion performed by a human figure.  In Study 1, infants and adults viewed an apparent motion stimulus comprising of an arm moving from one side of a leg to the other. Results showed that both infants and adults reacted with larger pupil dilation when observing an impossible apparent motion, that is, larger pupil dilation when it appears that a hand passed through the leg as opposed to moving around the leg. Study 2 found no such effect when 12-month-old infants observed an object control stimulus with perceptually similar properties. These findings suggest that apparent motion perception is context dependent and that the constraints of the human body and human actions are taken into account when perceiving rapidly changing static images as fluid motion.

Infants have an early understanding of giving (the transfer of an item by one agent to another), but little is known about individual differences in these abilities or their developmental outcomes. Here, 9-month-olds (N = 59) showing clearer neural processing (Event-related potential, ERP) of a give-me gesture also evidenced a stronger reaction (pupil dilation) to an inappropriate response to a give-me gesture, and at 2 years were more likely to give in response to a give-me gesture. None of the differences in understanding and production of giving-related behaviors were associated with other sociocognitive variables investigated: language, gaze-following, and nongiving helping. The early developmental continuity in understanding and production of giving behavior is consistent with the great importance of giving for humans throughout the life span.

Individual differences in their emotional context may differentially impact infants’ ability to selectively encode and learn from their environment. The current study takes an integrative approach in considering three emotional contexts that have independently been found to modulate infants’ allocation of selective attention: maternal negative affect, infant temperament, and an emotional face prime (the mother and a stranger’s face). The study looked at the effects of that these contexts had on 9-month-old infants’ performance on a subsequent eye-tracking visual search task. Results revealed that infants were faster to find the target after viewing their mother’s angry face or a fearful face, regardless of familiarity. When the mother reported high negative affect, infants’ visual search performance was increasingly impacted by a fearful face, resulting in significantly faster visual search times. The findings demonstrate that both immediate emotional face prime and the mother’s negative affect have the capacity to influence what infants attend to and consequently influence their processing of information in their environment.