Developmental changes in prefrontal cortex activation in children with or without autism spectrum traits on near-infrared spectroscopy.

In PARS-determined typically developed children, prefrontal cortex activation on NIRS correlated positively with age. In healthy volunteers without ASD but harboring autistic traits, prefrontal cortex activation was markedly lower than in normal counterparts. Our results provide biological evidence that ASD may be a pervasively distributed disorder.