Cerebral laterality in adolescent major depression.

This study tests the hypothesis that adolescents with major depression exhibit abnormalities in cerebral asymmetry previously found among adults. Perceptual asymmetry was assessed through tests of verbal and non-verbal dichotic listening in four groups - 48 adolescents with major depression, 22 adolescent comparisons with no history of Axis I disorders, 149 adults with major depression, and 57 comparison adults with no history of Axis I disorders. Data from adults have been previously reported. In both age groups, subjects with major depression were further divided based on the presence or absence of an anxiety disorder. Procedures used to collect perceptual asymmetry data in adolescents and adults were identical. In both age groups, depressed and healthy subjects showed perceptual asymmetry in expected directions for verbal and non-verbal dichotic tasks. Depressed and comparison subjects differed in performance on the Fused-Word Test, though these differences varied as a function of anxiety and developmental level. Relative to comparisons, both adolescents and adults with major depression exhibited an increased right ear/left hemisphere advantage for fused words. Adults but not adolescents with comorbid major depressive and anxiety disorders exhibited a reduced right ear/left hemisphere advantage for fused words. These findings suggest similarities and differences across development in the relationship between cerebral laterality and psychopathology. Further studies using longitudinal and family-based designs, as well as various measures of regional brain activity, are needed to enhance understanding of associations between cerebral laterality and psychopathology across development.