Pharmacopsychiatry 2003; 36 - 221
DOI: 10.1055/s-2003-825464

Sensorimotor gating and habituation of the startle reflex in schizophrenic patients treated with amisulpride or olanzapine compared to healthy controls

BB Quednow 1, M Wagner 1, J Westheide 1, W Maier 1, KU Kühn 1
  • 1University of Bonn, Department of Psychiatry

Patients with schizophrenia exhibit impairments in habituation and sensorimotor gating of the acoustic startle response (ASR). Despite of clear evidence of gating and habituation mechanisms in animal models, it is still unknown which neurotransmitter systems are involved in schizophrenia.

We investigated the influence of two antipsychotic agents with different receptor affinities on gating and habituation of ASR in patients with schizophrenia. ASR of 28 schizophrenic patients randomly and double-blind treated with amisulpride or olanzapine was assessed during the first week, after 4 and 8 weeks of treatment. 18 matched healthy controls were examined likewise.

Schizophrenic patients showed a gating deficit and decreased startle reactivity at baseline. The gating deficits disappeared after antipsychotic treatment independent of medication. Amisulpride sensitised the startle reactivity, whereas in the olanzapine group the decreased startle reactivity persisted. We could not demonstrate habituation deficits in schizophrenic patients. Regardless, amisulpride accelerated and olanzapine attenuated habituation across 8 weeks.