Sensorimotor gating and attitudes related to schizotypal proneness

The magnitude of the startle eyeblink response is diminished when the startle eliciting probe is shortly preceded by another stimulus. This so called prepulse inhibition is interpreted as an automatic sensorimotor gating mechanism. There is substantial support for prepulse inhibition deficits in subjects suffering from schizophrenia spectrum disorders and in psychosis-prone normals as well. Thus, prepulse inhibition deficits may reflect vulnerability on the hypothesized psychopathological continuum from "normal" to "schizophrenia." The present experiment investigated the amount of prepulse inhibition in a sample selected for "belief in extraordinary phenomena," an attitude related to measures of psychosis-proneness. Believers and skeptics were tested in an acoustic prepulse-inhibition paradigm. As expected presentation of prepulses clearly diminished magnitude of startle response, with greatest inhibition effects gained by lead intervals of 60 and 120 msec. Patterns of response were identical for believers and skeptics, i.e., attitude towards extraordinary phenomena did not seem to be related to functional information-processing deficits as has been observed in psychosis-prone normals.