[Quantitative EEG analysis and the value for differential diagnosis on depression: I. Spectral power and coherence analysis].

Spectral power and coherence analysis were taken on 47 depressive patients and 43 normal controls. Depressive patients showed abnormal brain activity mostly in frontal-central regions. The endogenous and manic-depressive groups mainly presented higher power of slow activity and predominant in right hemisphere, while the non-endogenous and other groups presented higher power mainly in the fast bands. Coherence analysis showed that the coherence of EEG between homogenous points of two hemispheres was decreased in depressed patients.