Reduced Visual Cortex Gray Matter Volume and Thickness in Young Adults Who Witnessed Domestic Violence during Childhood

Abstract

Exposure to interparental violence is associated with negative outcomes, such as depression, post-traumatic stress disorder and reduced cognitive abilities. However, little is known about the potential effects of witnessing domestic violence during childhood on gray matter volume (GMV) or cortical thickness. High-resolution 3.0 T volumetric scans (Siemens Trio Scanner) were obtained on 52 subjects (18–25 years) including 22 (6 males/16 females) with a history of visually witnessing episodes of domestic violence, and 30 (8 males/22 females) unexposed control subjects, with neither a current nor past DSM-IV Axis I or II disorder. Potential confounding effects of age, gender, level of parental verbal aggression, parental education, financial stress, full scale IQ, and total GMV, or average thickness were modeled using voxel based morphometry and FreeSurfer. Witnessing domestic violence subjects had a 6.1% GMV reduction in the right lingual gyrus (BA18) (P = 0.029, False Discovery Rate corrected peak level). Thickness in this region was also reduced, as was thickness in V2 bilaterally and left occipital pole. Theses regions were maximally sensitive to exposure to witnessing domestic violence between 11–13 years of age. Regional reductions in GMV and thickness were observed in both susceptible and resilient witnessing domestic violence subjects. Results in subjects witnessing domestic violence were similar to previously reported results in subjects with childhood sexual abuse, as the primary region affected was visual cortex. Brain regions that process and convey the adverse sensory input of the abuse may be specifically modified by this experience, particularly in subjects exposed to a single type of maltreatment. Exposure to multiple types of maltreatment is more commonly associated with morphological alterations in corticolimbic regions. These findings fit with preclinical studies showing that visual cortex is a highly plastic structure.

Neuroanatomical Correlates of Childhood Sexual Abuse: Identifying Biological Substrates for Environmental Effects on Clinical Phenotypes

“…They suggest that such changes relate to the child’s sensory processing of the abusive experience, which alters cortical representation fields in a regionally specific fashion, based on the nature of the abuse itself. This finding comports with another recent work in which young adults, compared with an unexposed group, who witnessed domestic violence as children had decreased visual cortex gray matter (15), in terms of both volume and cortical thickness, regardless of whether or not they developed psychopathology. In addition, Heim et al noted that age at onset, although not severity of childhood sexual abuse, was related to cortical thinning in the left temporal pole, the left parietal lobe, the left frontal pole, and the right frontal pole, areas associated with autobiographical memory among other functions.…”

“…Cortical thinning was found to be present in the brain areas involved in the perception or processing of behaviors that are specific to the type of abuse experienced. For example, childhood sexual abuse was associated with cortical thinning in the genital representation field of the primary somatosensory cortex, whereas emotional abuse was associated with cortical thinning in regions linked to self-awareness and self-evaluation (15). The authors conclude that cortical adaptation to traumatic events may lead to decreases in the density of dendritic spines, leading to cortical thinning.…”

Sensitive periods of amygdala development: The role of maltreatment in preadolescence

“…While random forest regression is well-suited to identify ages when severity of exposure has the most important predictive effect on morphology (58, 59), we also sought to determine whether the magnitude of importance at peak periods could have occurred by chance. Hence, we used a re-randomization test in which we calculated the maximal increase in MSE with severity of exposure at any age in the original data set, and then tested for this degree of increase in MSE in 10,000 alternative random forests regressions in which the association between regional volume and exposure histories was randomly reshuffled.…”

The possible long-term effects of early-life circadian rhythm disturbance on social behavior

“…In addition, according to Tomoda et al, exposure to multiple types of maltreatment (sexual abuse, domestic violence) during childhood could be associated with morphological alterations in corticolimbic regions [81,82]. Sleep/circadian rhythm disturbance during the early stage of life may affect brain morphology.…”