The Reward Endophenotype in Autism: Implications for Understanding Affective, Cognitive, and Behavioral Function Across the Spectrum

Abstract

Studies of genetics and neural structure and function have implicated reward circuitry in the pathogenesis of autism spectrum disorders (ASD). Consequences of atypical reward have been studied most thoroughly in the context of the social motivation theory of autism to describe the lack of development of socio-communicative behaviors in ASD. Recent research indicates alterations in reward processing may also play a role in both the development restricted, repetitive behaviors and interests and the presence of certain co-morbid diagnoses in ASD. My dissertation studies have sought to address how alterations in reward processing may contribute to the development of two such clinical features in ASD, namely, restricted interests, which may be pathognomonic of ASD, and highly prevalent co-morbid diagnoses of depression. To this end, I have worked to modify / develop novel tasks to quantify attentional and motivational biases to specific types of nonsocial and affective information, using behavioral phenotyping, eye-tracking, and EEG. Overall results indicate that reward processing in ASD may be characterized by a nonsocial bias that is present early in development and across a range of functional ability and may interfere with processing of social reward. Further, altered reward processing may guide motivational biases that confer risk for co-morbid depression in ASD.