Startle response in inpatients with borderline personality disorder vs. healthy controls.

Startle response is found to be enhanced in conditions that are accompanied by intense emotions, high levels of anxiety in particular. We assessed the autonomous and behavioral component of the startle reflex in a sample of 28 unmedicated inpatients with borderline personality disorder (BPD) compared to 28 controls. Amplitudes of electrodermal and startle response as well as habituation were measured in response to 15 bursts of white noise (100-db, 40-ms). We assessed prepulse inhibition to study gating capacities in BPD, with each prepulse (70-db, 30-msec) delivered 100 ms before the startling tone. In contrast to our hypothesis, our study revealed neither enhanced amplitudes of autonomic and electromyographic startle responses nor differences in habituation compared to healthy controls. In addition, no deficit in prepulse inhibition was found in BPD. In summary, our data indicate normal response to unconditioned threatening stimuli as well as normal gating capacities in BPD.