Autism is characterized by qualitative impairments in social interaction, communication, and stereotyped repetitive behaviors and/or restricted interests. Beyond these diagnostic criteria, autism is viewed as a neurodevelopmental condition with possibly several etiologies that manifest in complex patterns of atypical structural and functional brain development, cognition, and behavior. Despite the multidimensional nature of and substantial variation within the autism spectrum, impairments in social interaction remain among the most visible hallmarks of the condition. It is this profound developmental deficit in the social domain that makes autism a unique case in the field of social neuroscience. This chapter contributes to the dialogue amongst both the fields of autism research and social neuroscience by deliberately taking the stance of asking how we can understand more about the etiological mechanisms underlying social behavior in autism. It presents a multi-level overview of the literature on the behavioral, neural, and genetic underpinnings of social functioning in autism spectrum conditions (ASC). The main objective is to highlight the current state of the field regarding theory of mind/empathy difficulties in ASC, and then to suggest distinct candidate neural endophenotypes that can bridge the gap between social behavior and genetic mechanisms
