Reduced Somatomotor Cortical Thickness in Women With PTSD After Childhood Sexual Abuse: A Structural Correlate Distinct From Adult Sexual Dysfunction.

BACKGROUND: Childhood sexual abuse (CSA) is a major risk factor for posttraumatic stress disorder (PTSD) and adult sexual dysfunction in women. Although adverse childhood experiences have been linked to altered brain structure, cortical alterations specifically associated with CSA and PTSD in women remain poorly characterized, and their relationship to adult sexual functioning is unknown.

METHODS: Women with CSA and current PTSD (n = 52), women with CSA without current PTSD (n = 32), and control women without CSA or PTSD (n = 48) underwent structural magnetic resonance imaging. Cortical thickness, surface area, and cortical volume were examined using whole brain vertex wise analyses. Sexual functioning was assessed in a subsample (n = 41).

RESULTS: Women with CSA and current PTSD showed reduced cortical thickness within a left somatomotor cluster relative to controls (cluster wise p = .017). Anatomical characterization localized the cluster to motor and premotor regions involved in bodily self representation and sensorimotor integration. No group differences were observed in cortical surface area or volume. Women with CSA and PTSD also reported lower sexual functioning, particularly in arousal, lubrication, satisfaction and pain. Cortical thickness within the somatomotor cluster was unrelated to sexual functioning and did not mediate the association between CSA severity and sexual dysfunction.

CONCLUSIONS: These findings suggest that somatomotor cortical alterations represent neurobiological correlates of trauma related psychopathology following CSA in women. The absence of associations with adult sexual functioning suggests that structural alterations within the somatomotor cortex may be distinct from mechanisms contributing to sexual dysfunction.