Use of translational neuroscience approaches in young children for understanding social motivation heterogeneity. - ABSTRACT This project will examine the neurobiological mechanisms that drive heterogeneity in social behavior across development. Two theories for how disruptions in social interactions may arise have been proposed, but neither has won complete acceptance. The two theories are: 1) Social interaction may be unpleasant for some children, possibly aversive and fear-inducing. Modulated in a state-dependent manner, this aversion may drive a lack of social engagement. 2) Social interaction for some children is not aversive, but neither is it motivating. Our central hypothesis is that neither of these two theories alone fits an entire population of children. Instead, we propose that there is a continuum of social motivation and that categorizing children along this continuum will advance identification of the neurobiological mechanisms driving social behavior. To test our hypothesis, we will quantify children’s attention to, and motivation for, social stimuli by combining eye-tracking with conditioned place preference (CPP), a well-established technique from animal studies. Importantly, our eye- tracking and CPP methods do not depend on a child’s language ability, allowing populations with limited or disrupted language to also participate. Our social CPP (sCPP) protocol will reveal the underlying mechanisms driving social motivation and allow us to characterize the heterogeneity in social motivation across development in young children. Eye-tracking will elucidate the saliency of and attention to social stimuli in these same children. Impact: This project is significant because clearly identifying the dynamics that underlie social motivation for each child will be a breakthrough in understanding behaviors that are disrupted across many diagnostic groups. The knowledge gaps today in understanding the neurobiological mechanisms for altered social behaviors greatly limit the ability to design effective interventions to improve disrupted social behavior. Revealing mechanistic factors underlying these potential behavioral subgroups by combining eye-tracking and sCPP behavior tasks will significantly impact our understanding of the neurobiology of social motivation in young children, the clinical assessment of children with disruptions in social behaviors, and ultimately the future design of individually tailored interventions to help them.
