Prepulse Modification of the Acoustic Startle Reaction in Healthy Subjects and Patients with Schizophrenia

The characteristics of prepulse inhibition (PPI) and prepulse facilitation (PPF)of the acoustic startle reaction (ASR) were studied in healthy subjects and patients with schizophrenia. Testing was performed in accordance with the recommendations of the International Schizophrenia Genetics Consortium. Patients showed a deficit in PPI with a prepulse interval of 60 msec and suppression of PPF with an interval of 2500 msec, demonstrating impairments of undirected attention. Differences were seen in the effects of histories of craniocerebral trauma and experience of consumption of psychoactive substances on PPI and PPF in healthy subjects and patients. Correlations between baseline ASR and increases in excitement (PANSS scale P4) and between impairments to PPF and the severity of positive symptomatology were seen. The results obtained here provide evidence that the prepulse ASR modification test can be used in clinical neurophysiology.