Dysfunction in smooth pursuit eye movements and history of childhood trauma

Several commentators recently have advocated the view that a deficit in the performance of a smooth pursuit eye-movement task is a biological marker of the genetic predisposition to schizophrenia. This study considered the possibility that such an impairment is due in part to experiential or acquired characteristics, and specifically, to a history of childhood trauma. A sample of 100 Australian adults performed a visual tracking task and completed a self-report measure of childhood trauma. Although the effect size was small, a relationship was found between eye-tracking performance and a childhood history of physical and emotional abuse. This finding suggests that eye-tracking performance may not be governed entirely by genetic factors, a possibility that has implications for the use of indices of smooth pursuit eye movement as a purely genetic marker of proneness to schizophrenia. Further investigation is needed to clarify the basis of the association between these deficits and childhood abuse.