Amygdala Volume and Social Reward in Children with and without Autism Spectrum Disorder

Abstract

Social interaction is a vital part of our everyday life and while there have been many studies that have helped elucidate both the neural components and extrinsic factors of these processes, it is still something that is not completely understood. This is especially relevant to those with Autism Spectrum Disorder (ASD), as they are often characterized as having social processing deficits. Social cognition is one of the many functions associated with the limbic system, along with reward and emotion processing. Previous studies have shown that social interaction is rewarding and has been shown to activate regions in the limbic system (Warnell et al., 2017). The amygdala is a region included in social/reward circuitry within the limbic system, such that larger amygdala volumes have been associated with higher connectivity within these regions (Bickart et al., 2012). There have not been previous studies to our knowledge assessing how amygdala volume and social reward sensitivity may vary together, motivating the current study. Therefore, this study aims to assess how social reward relates to amygdala volume in 49 children (ASD = 21, TD = 31) aged 8 to 14 with and without a diagnosis of ASD. Social reward will be assessed using the Prosocial Interactions and Sociability subscales of the Social Reward Questionnaire (SRQ; Foulkes et al., 2014). Amygdala volumes were extracted using MRICloud (Mori et al., 2016). Amygdala size and SRQ subscale differences between groups will be analyzed using an analysis of covariance (controlling for total gray matter) and an independent samples t-test, respectively. A regression analysis will be conducted in order to examine amygdala and SRQ associations.