Die Alpha-Asymmetrie als Responseprädiktor in der antidepressiven Therapie ; The alpha-asymmetry as a response predictor in antidepressive therapy

The frontal alpha-asymmetry has been labeled to be a psychophysiological correlate in unipolar depression and a possible biomarker for therapy response. Aim of this study was to compare depressive patients with healthy controls and to determine differences between responders and nonresponders due to changes in the alpha-asymmetry before and after starting an antidepressive therapy as a predictor of therapy response. Therefore 45 participants with unipolar depression were observed until a possible response after four weeks of medicamentous antidepressive therapy by rating depressive symptoms on the HAMD. EEG-measures were conducted prior to start of therapy and one week after. An Emotional-Face-Stimulus-Test including negative and positive visual stimuli was presented. Both alpha1- (8-10,5Hz) and alpha2-asymmetry (10,5-13Hz) were calculated. Patients with depressive disorder showed a left-frontal lateralization of alpha1- and alpha2-frequencies in contrast to a right-frontal lateralization in controls during positive and negative visual stimuli. This confirmed the assumption of left-frontal cortical hypoactivity in depression. The analysis of subgroups revealed an increase of right-frontal cortical activity during negative visual stimuli in responders after one week of antidepressive therapy. The left-frontal lateralization of alpha1-frequencies could be a predictor of later therapy response. Further research with larger patient samples is needed to confirm these results. ; Gegenstand der vorliegenden Arbeit ist die frontale Alpha-Asymmetrie als pathophysiologisches Korrelat bei der unipolaren Depression und als möglicher Biomarker für eine Therapieresponse. Ziel war neben einem Vergleich von depressiven Patienten und gesunden Kontrollen auch die Feststellung eines Unterschiedes zwischen Therapierespondern und Nonrespondern anhand der Änderung der Alpha-Asymmetrie während des Beginns einer medikamentösen antidepressiven Therapie zur Prädiktion einer Therapieresponse. Dafür wurden 45 Probanden mit unipolarer ...