Activation in the prefrontal cortex during facial expression processing in pervasive developmental disorder using near-infrared spec-troscopy

Abstract

One of the most characteristic impairments in social communication in pervasive developmental disorders (PDD) is the failure to perceive and respond to non-verbal conversational cues such as facial expression. We found out that healthy subjects had significantly increased oxyHb changes during a processing task of fearful expression compared to happiness in the prefrontal cortex (PFC) and found significant correlations between oxyHb change in PFC and Autism-Spectrum Quotient score using near-infrared spectroscopy (NIRS). Moreover, we showed that 14 patients with PDD had significantly reduced oxyHb changes in PFC during a processing task of fearful expression compared to 14 age-and sex-matched healthy controls. NIRS could be one of the most powerful tools for PDD research, because it has advantages in convenience, non- invasiveness and less of psychological and physical burden.