Previous accounts of the development of triadic attention identify a "curious" shift around nine to twelve months. We introduce a novel approach inspired by distributed and embodied cognition frameworks. In a longitudinal study of five mother-infant dyads, videos of home play interactions were recorded over the infants' first year. We scrutinized the real-time organization of mother-infant sensorimotor activity, including the targets of hands, gaze, and mouth, as the dyad members attended to one another and to toys. We identified a pervasive developmental pattern: At four months, infants converged all sensory modalities on objects introduced by the mother. From six to twelve months, infants showed increasing decoupling of hands and eyes and increasingly elaborate sequences in multi-object play. Concurrently, dyads engaged in increasingly elaborate social exchanges (e.g., turn-taking) as mothers adapted to infants' sensorimotor skills. We therefore theorize that triadic attention emerges not as a novel form of social cognition but as a continuous product of sensorimotor development, scaffolded by parents' expanding social actions. © 2013 S. Karger AG, Basel.

A current theory of attention posits that several micro-indices of attentional vigilance are dependent on activation of the locus coeruleus, a brainstem nucleus that regulates cortical norepinephrine activity (Aston-Jones , 1999). This theory may account for many findings in the infant literature, while highlighting important new areas for research and theory on infant attention. We examined the visual behaviors of n=16 infants (6-7months) while they attended to multiple spatially distributed targets in a naturalistic environment. We coded four measures of attentional vigilance, adapted from studies of norepinergic modulation of animal attention: rate of fixations, duration of fixations, latency to reorientation, and target 'hits'. These measures showed a high degree of coherence in individual infants, in parallel with findings from animal studies. Results also suggest that less vigilant infants showed greater habituation to the trial structure and more attentiveness to less salient stimuli during periods of high attentional competition. This pattern of results is predicted by the Aston-Jones model of attention, but could not be explained by the standard information processing model. © 2011 Blackwell Publishing Ltd.

Infants are biologically prepared to learn complex behaviors by interacting in dynamic, responsive social environments. Although the importance of interactive social experiences has long been recognized, current methods for studying complex multimodal interactions are lagging. This paper outlines a systems approach for characterizing fine-grained temporal dynamics of developing social interaction. We provide best practices for capturing, coding, and analyzing interaction activity on multiple-temporal scales, from fractions of seconds (e.g., gaze shifts), to minutes (e.g., coordinated play episodes), to weeks or months (e.g., developmental change). © 2013 IEEE.