The Usefulness of the Auditory N100 and P200 Component as Measures of Sensory Gating

A sensory gating deficit has been repeatedly demonstrated in schizophrenia patients, especially for the P50 component of the auditory evoked response. In the present study, we investigate whether the N100 and P200 can be used as gating measures as well, and what kind of differences exist between normal controls and schizophrenia patients for these gating measures. We also explore whether gating is absent when sequences of non-identical stimuli are presented. It was found N100 and P200 showed significantly more gating and less day-to-day variability than P50 for normal subjects. Large day-to-day and inter-subject variability was observed in schizophrenia patients. The gating indexes for the non-identical stimuli were not significantly different from the corresponding indexes for identical stimuli