Oxytocin and autism

Introduction: Over the past three decades, growing research has implicated an association between the peptide hormone oxytocin (OT) and autism spectrum disorders (ASD) due to the increasingly documented involvement of OT in the regulation of social and repetitive behaviors (Modahl et al., 1992; Panksepp, 1992; Waterhouse et al., 1996; McCarthy and Altemus, 1997; Insel et al., 1999; Hollander et al., 2003; Lim et al., 2005; Hollander and Bartz, 2006; Carter, 2007; Bartz and Hollander, 2008; Guastella et al., 2008; Gregory et al., 2009; Guastella et al., 2010). In this chapter, we review research to date that has investigated the relationship between OT and the presentation or regulation of several key deficits associated with ASD. First, we provide an overview of ASD and of OT, followed by a brief review of the current theories surrounding the etiology of the disorder. Next, we review genetic research of the oxytocin receptor gene (OTR) followed by an overview of experimental therapeutic research involving the administration of OT in individuals with ASD. Finally, suggestions for directions that future research should address are discussed. Of note, only minimal animal and translational research is reviewed, as it can be found discussed at length elsewhere in the present volume. Autism spectrum disorder ASD refers to a group of neurodevelopmental disorders (autistic disorder, Asperger Syndrome and pervasive developmental disorder not otherwise specified) characterized by deficits within three core symptom domains: social interaction, speech and communication, and repetitive or compulsive behaviors with restricted interests. Formal DSM-IV diagnostic criteria for autistic disorder can be found in Textbox 20.1.