P50 gating deficit in Alzheimer dementia correlates to frontal neuropsychological function

Thomas, Christine; vom Berg, Ingo; Rupp, Andre; Seidl, Ulrich; Schröder, Johannes; Roesch-Ely, Daniela; Kreisel, Stefan H.; Mundt, Christoph; Weisbrod, Matthias

doi:10.1016/j.neurobiolaging.2008.05.002

« Previous Next »Neurobiology of Aging
Volume 31, Issue 3 , Pages 416-424, March 2010

P50 gating deficit in Alzheimer dementia correlates to frontal neuropsychological function

Christine Thomas
- Centre for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Voßstr. 2, 69115 Heidelberg, Germany
- Department of Geriatric Psychiatry, Centre of Psychiatry and Psychotherapy, Ev. Hospital Bielefeld-Bethel, Bethesdaweg 12, 33617 Bielefeld, Germany
- Corresponding author at: Abteilung für Gerontopsychiatrie, Klinik für Psychiatrie und Psychotherapie Bethel, Evangelisches Krankenhaus Bielefeld, Bethesdaweg 12, 33617 Bielefeld, Germany. Tel.: +49 521 772 78695; fax: +49 521 772 78698.
Ingo vom Berg
- Centre for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Voßstr. 2, 69115 Heidelberg, Germany
Andre Rupp
- Section of Biomagnetism, Department of Neurology, University of Heidelberg, INF 400, 69126 Heidelberg, Germany
Ulrich Seidl
- Centre for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Voßstr. 2, 69115 Heidelberg, Germany
Johannes Schröder
- Centre for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Voßstr. 2, 69115 Heidelberg, Germany
Daniela Roesch-Ely
- Centre for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Voßstr. 2, 69115 Heidelberg, Germany
Stefan H. Kreisel
- Department of Geriatric Psychiatry, Centre of Psychiatry and Psychotherapy, Ev. Hospital Bielefeld-Bethel, Bethesdaweg 12, 33617 Bielefeld, Germany
Christoph Mundt
- Centre for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Voßstr. 2, 69115 Heidelberg, Germany
Matthias Weisbrod
- Centre for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Voßstr. 2, 69115 Heidelberg, Germany
- Department of Psychiatry, SRH Klinikum, Karlsbad-Langensteinbach, Germany

Received 14 January 2008; received in revised form 21 April 2008; accepted 1 May 2008. published online 18 June 2008.

Abstract

Background

Cognitive inhibition processes were found to be deficient early in the clinical course of Alzheimer's disease (AD). The inhibition of redundant information is a precondition for efficient cognitive processing and presumably modulated by prefrontal attentional networks. Deficits in the suppression of the evoked potential P50 response to paired clicks are well known in schizophrenic patients and undergo cholinergic modulation. In this study, we aimed to investigate inhibitory gating deficits of P50 in AD and their relation to neuropsychological measures.

Method

P50 suppression was assessed in 19 AD-patients in comparison to a young and elderly control group (n=17 each) and related to MMSE and specific neuropsychological assessments.

Results

Patients showed reduced sensory gating compared to healthy elderly (p<0.021) and exhibited significantly higher N40-P50-amplitudes. There were no age or gender effects in controls. Frontal neuropsychological tests (TMT-B, verbal fluency) and working memory requiring inhibition, but not declarative memory functions, were significantly correlated with inhibitory gating and test amplitude in both, AD-patients and controls.

Conclusions

The results support an early inhibitory deficit interfering with executive functions and working memory in AD independent from physiological aging. P50 gating might be applicable as a marker for inhibition deficits and thereby be important for prognosis estimation.

Keywords: Auditory sensory gating, Alzheimer's disease, Aging, Frontal inhibition, Auditory evoked potentials