Ga. Light et Dl. Braff, Do self-reports of perceptual anomalies reflect gating deficits in schizophrenia patients?, BIOL PSYCHI, 47(5), 2000, pp. 463-467
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 inund
ation had normal levels of P50 suppression whereas patients who tended to e
ndorse fewer complaints of perceptual anomalies had P50 suppression deficit
s,Jin et al's finding challenges the common belief that P50 suppression def
icits are associated with cognitive and sensory anomalies reflecting poor g
ating in schizophrenia patients. This article comments on how the dissociat
ion between phenomenological experiences of gating disturbances and P50 sup
pression might be explained by the limits of self-report in schizophrenia p
atients who have deficient insight and self-awareness. We hypothesize that
the self-reported inability to screen out irrelevant stimuli reflects a vol
untary, controlled process that is different from the involuntary, automati
c process measured by P50 suppression. (C) 2000 Society of Biological Psych
iatry.