Commentary: Complementary approaches to the developmental cognitive neuroscience of autism - reflections on Pelphrey et al. (2011)

Abstract

Autism spectrum disorders (ASDs) are currently defined on the basis of observable behavior, with diagnostic criteria allow for enormous heterogeneity. In principle, two hypothetical individuals can receive a diagnosis of ‘‘autistic disorder’’ despite evidencing entirely non-overlapping symptoms. There is a growing sense that this heterogeneity stands as a major obstacle to further progress in understanding the causes of ASDs. In the current issue, however, Pelphrey, Hudac, Schulz & Vander Wyk (2011) argue that researchers have ‘‘over-emphasised the heterogeneity in ASD’’ by failing to recognize ‘‘the homogeneity of core disruptions in social information processing’’. Focusing on brain regions implicated in social cognition, they suggest, will ‘‘constrain’’ the heterogeneity problem. In what follows, I outline some of the challenges for this approach to autism and advocate a complementary research strategy that seeks instead to capitalize on autistic heterogeneity. Autism is classified as a pervasive developmental disorder, affecting multiple aspects of cognition and behaviour. While it makes sense to constrain the research question by seeking a good explanation of a specific aspect of the disorder, this is not the same as constraining autism itself. Some form of social impairment is required for an autism diagnosis, entailing that social dysfunction is a universal amongst diagnosed individuals. Although Pelphrey et al. (2011) acknowledge that the nature of this social impairment can vary considerably, they suggest that the underlying neurobiological mechanisms may be common to all or most individuals on the autism spectrum. Given the complexity of our social cognitive apparatus and the many potential ways in which its development could go awry, strong evidence is required before such an assertion can be made.