Do self-reports of perceptual anomalies reflect gating deficits in schizophrenia patients?

Jin and colleagues presented an innovative study examining P50 suppression and patients' self-reported perceptual anomalies as two related operational measures of sensory gating deficits in schizophrenia patients. They found that those schizophrenia patients who endorsed experiences of sensory inundation had normal levels of P50 suppression, whereas patients who tended to endorse fewer complaints of perceptual anomalies had P50 suppression deficits. Jin et al's finding challenges the common belief that P50 suppression deficits are associated with cognitive and sensory anomalies reflecting poor gating in schizophrenia patients. This article comments on how the dissociation between phenomenological experiences of gating disturbances and P50 suppression might be explained by the limits of self-report in schizophrenia patients who have deficient insight and self-awareness. We hypothesize that the self-reported inability to screen out irrelevant stimuli reflects a voluntary, controlled process that is different from the involuntary, automatic process measured by P50 suppression.