Evoked potential evidence for right brain activity during the recall of traumatic memories

Abstract

Auditory probe evoked potential attenuation was measured as an index of hemispheric activity in 10 subjects with a history of childhood trauma and 10 matched subjects without such history while they recalled a neutral memory and then a traumatic memory. There were prominent group differences in degree of cerebral laterality between memory tasks (P = 0.02). The trauma group had a significant left dominant asymmetry during the neutral memory (P = 0.02), which markedly shifted to the right during the unpleasant memory (P = 0.007 for degree of shift). Normal control subjects did not display a significant asymmetry during either task, nor did they show a significant shift between tasks.