Quantitative EEG in elderly depressives.

Thirty-one elderly depressive patients were evaluated with topographic, quantitative EEG using relative measures, absolute measures, and computations of interhemispheric asymmetry and interhemispheric coherence in four frequency bands: delta, theta, alpha and beta. Patients were found to have lower than normal delta, higher than normal theta, higher than normal alpha and lower than normal beta values. EEG values were greater over the left than the right hemisphere in theta, alpha and beta bands. Lower than normal anterior interhemispheric coherence was found in all four frequency bands.