ABNORMAL VISUAL CORTICAL DEVELOPMENT IN YOUNG WOMEN WITH A HISTORY OF REPEATED CHILDHOOD SEXUAL ABUSE: A VOXEL-BASED MORPHOMETRIC STUDY

Objectives: Childhood sexual abuse (CSA) is common in our society and a major risk factor for later psychopathology. Recent reports have described the long-term effects of CSA on brain structure. Key findings include frontal lobe and superior temporal gyrus asymmetry attenuation and volumetric reductions of the prefrontal cortex and prefrontal white matter, hippocampus, and corpus callosum. Little is specifically known about the effects of CSA on gray matter volume (GMV), and an objective overall assessment using voxelbased morphometry (VBM) has yet to be reported.

Methods: To elucidate effects of CSA on GMV, we conducted optimized VBM in 23 unmedicated collegiate females with a history of repeated CSA and 14 psychiatrically healthy female controls with no history of exposure to traumatic events. We used a high-resolution T1-weighted MRI data set and subjects were imaged volumetrically at 1.5 T.

Results: We observed a significant reduction in GMV in the left visual cortex (L-V1 and L-V2) of abused subjects (P<0.0001, corrected). In comparison with healthy controls, there was an average of 14.1% GMV reduction in the abused subjects. A cortical surface-based analysis also revealed that GMV of abused subjects were significantly smaller than that of controls in the left visual cortex (P=0.007).

Conclusion: CSA may degrade visual cortical development in young adults who are sufficiently healthy to matriculate. These findings point to the possibility that traumatic experience may modify brain structure at the level of sensory cortex itself.