OUTCOME OF COGNITIVE-BEHAVIORAL THERAPY FOR DEPRESSION - RELATION TO HEMISPHERIC DOMINANCE FOR VERBAL PROCESSING

Unmedicated depressed outpatients were tested on dichotic syllable and complex tone tests prior to receiving 16 weekly sessions of cognitive therapy (n = 31) or 6-12 weeks of placebo treatment (it = 45). Cognit ive-therapy responders had twice the right-ear (left hemisphere) advan tage for syllables when compared with nonresponders but did not differ from nonresponders on the nonverbal task. The larger right-ear advant age in cognitive-therapy responders was due to better right-ear accura cy; they did not differ from nonresponders in left-ear accuracy. No di fferences in perceptual asymmetry or accuracy were found between place bo responders and nonresponders. Right-ear accuracy for syllables was the best predictor of response to cognitive therapy in a logistic regr ession analysis. The findings suggest that greater left-hemisphere adv antage for verbal processing is associated with more favorable outcome of cognitive therapy for depression.