Realizing the translational promise of psychophysiological research in ASD.

This special issue of the Journal of Autism and Developmental Disorders focuses on the contributions of psychophysiological research to scientific understanding of autism spectrum disorder (ASD). The past decade has brought considerable advances in the application of psychophysiology for examining mechanisms of function and dysfunction in ASD. These insights span the range of behaviors affected, including social communication, restricted and repetitive behaviors, sensory processing, and cognition. Psychophysiological methods hold promise to offer key insights into autism by elucidating the biological underpinnings of behavior, by informing clinical understanding through more nuanced characterization of the phenotype, and by guiding intervention via describing treatment targets, predicting response to intervention, and measuring outcomes. The current issue reflects the breadth and depth of these approaches to ASD by presenting in a single volume a range manuscripts employing electrophysiology, electromyography, cardiac measures, magnetoencephalography, and electrodermal response. The studies described in this special issue address scientific questions related to social perception, sensory attention, interpersonal responsivity, social ability, memory, language, and other areas, and the populations involved in this work range from infants to adults with ASD, typical development, and other neurodevelopmental disorders such as tuberous sclerosis and ADHD. The adoption of and enthusiasm for these techniques by ASD researchers is evident in the overwhelming response to our call for papers. A competitive review process yielded 25 outstanding manuscripts, representing the state of the science in psychophysiological ASD research. We are grateful to the editorial staff at Springer for embracing this enthusiasm and kicking off 2015 with publication of this “super issue” that exceeds standard limits for special issues or sections. Psychophysiology is established as a critical component of ASD research, informing early detection, yielding insight into markers of dysfunction across symptom domains, and illuminating response to treatment. In the first work to document predictors of diagnostic outcome in infants at-risk for ASD, Elsabbagh and colleagues used event-related potentials (ERPs) to detect neural responses to eye gaze at 6–10 months of age that predicted subsequent ASD diagnosis at 36 months of age (Elsabbagh et al. 2012). Psychophysiological approaches have revealed markers of dysfunction across multiple domains related to autism. In terms of social behavior, McPartland and colleagues capitalized on the temporal resolution of electrophysiology to reveal delayed neural responses to faces in individuals with autism (McPartland, Dawson, Webb, Panagoitides, and Carver 2004). Roberts and colleagues shed light on identified delays in the M100 component in response to simple sensory information in individuals with autism, suggestive of a psychophysiological endophenotype for autism (Roberts et al. 2010). By examining skin conductance response, South and colleagues demonstrated an association between autonomic response to a simple discrimination conditioning task and autism symptom severity, informing the neural functioning of structures implicated in fear conditioning in autism (South, Larson, White, Dana, and Crowley 2011). Analysis of spectral EEG power has helped explain dysfunction in action execution/observation in autism and elucidate the relationship between neural functioning and imitative ability (Bernier, Dawson, Webb, and Murias 2007; Bernier, Aaronson, and McPartland 2013). Finally, the application of electrophysiology to autism intervention has provided initial evidence of brain changes in response to behavioral intervention, highlighting the efficacy of treatments based on behavior analytic principles to specifically target and improve the efficiency of brain mechanisms involved in social behavior (Dawson et al. 2012). These and the many other innovative applications of psychophysiology to autism research highlight the significant contributions and essential role of these approaches to informing our understanding of ASD. This special issue highlights the wide application and utility of these methodologies for creating innovative, insightful, and practically informative science.