Perceptual asymmetry differences between major depression with or without a comorbid anxiety disorder: A dichotic listening study

Predictions that anxious and nonanxious depression would differ in perceptu al asymmetry (PA), as well as in sensitivity for perceiving emotional words , were evaluated using dichotic listening tasks. A total of 149 patients ha ving a major depressive disorder (51 with and 98 without an anxiety disorde r) and 57 healthy controls were tested on fused-word and complex tone tasks . The anxious and nonanxious depression groups showed a consistent differen ce in PA across tasks; that is, the anxious group had a larger left-ear adv antage for tones and a smaller right-ear advantage for words when compared with the nonanxious group. There was no group difference in sensitivity for perceiving emotional words. Patients having an anxious depression appear t o have a greater propensity to activate right than left-hemisphere regions during auditory tasks, whereas those having a nonanxious depression have th e opposite hemispheric asymmetry.