Female schizophrenia patients have prepulse inhibition deficits

Background Prepulse inhibition (PPI) of startle shows sexual dimorphism: women have lower levels of PPI than do men, and have menstrual cycle shifts in PPI. Many studies report PPI deficits in male schizophrenia patients; one recent report identified PPI deficits in male but not female patients. This study was designed to determine whether female schizophrenia patients have lower levels of PPI than normal females. Methods Twenty-five female schizophrenia patients, and 26 normal females were tested in a startle paradigm using 115 dB startle pulses and prepulses of 8 and 16 dB above a 70 dB background, with 30 and 120 msec prepulse intervals. Results Female patients had significantly less PPI compared with normal females, particularly when 16 dB prepulses were utilized. Patients also exhibited a nonsignificant trend towards lower levels of habituation compared to normal subjects. Conclusions Under the present paradigmatic and subject acquisition conditions, female schizophrenia patients had PPI deficits compared to normal females.