Normal P50 Gating in Children With Autism.

Background: An important characteristic of children with autism is their unusual reaction to stimuli, which may be related to problems in the filtering of sensory input. For this reason, sensory filtering was measured in children with autism using the P50 gating paradigm.

Method: Twelve non-mentally retarded children with autism (i.e., having a DSM-IV diagnosis of either autistic disorder or pervasive developmental disorder not otherwise specified) and 11 healthy control children were tested for their ability to suppress P50, measured at the Cz electrode.

Results: No differences were found between the children with autism and the control children with regard to absolute P50 amplitudes and P50 suppression.

Conclusion: The excitability of the neuronal substrate that causes P50 is normal in children with autism, as are the early, inhibitory processes related to P50 gating. These results distinguish between subjects with autism and subjects with schizophrenia, in whom sensory gating is abnormal.