The intensity dependence of the auditory evoked N1/P2-ERP-component increases in pharmacotherapy of major depression with citalopram

Objective: The stimulus intensity (loudness) dependence of the auditory

N1-ERP-component (IDAP) has been suggested as an indicator of central

serotonergic neurotransmission with relevance to pharmacological treatment.

Here we report first results of a controlled study evaluating the IDAP in the course of psychopharmacological treatment of major depressive disorder (DSM-IV) with an SSRI.

Method: IDAP was assessed three times in 18 inpatients (prior to antidepressive pharmacotherapy, after 5 and after 24 (mean) days of citalopram-treatment) and two times in 35 matched healthy control subjects (21 to 28 days time interval). Clinical symptoms of depression were assessed by means of psychiatric rating scales(CGI, HAMD, BDI).

Results: Patients’ mean HAMD score was 24 (sd=4.2) at baseline and 8 (sd=4.8) after 24 (mean) days. The Amplitude of N1/P2-ERP-component increased from 0.91µV/10db to 1.21µV/10db.

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