Childhood maltreatment experiences are associated with altered diffusion in occipito-temporal white matter pathways

Childhood maltreatment may contribute to brain alterations in posttraumatic stress disorder (PTSD). We previously found that PTSD was associated with white matter compromise, or lower fractional anisotropy (FA), in the left inferior longitudinal fasciculus (ILF). In this study, including non-PTSD controls, we examined whether ILF FA was associated with maltreatment exposures, including those that meet DSM-IV criterion A (physical abuse, sexual abuse) and those that typically do not (emotional abuse, emotional neglect, physical neglect). We hypothesized that lower FA would be associated with PTSD diagnosis and with both categories of maltreatment.

Ninety-three participants (51 female), ages 20-50, were enrolled, including 32 with lifetime DSM-IV PTSD, 27 trauma-exposed non-PTSD controls, and 34 healthy controls. Participants completed structured interviews, the Childhood Trauma Questionnaire (CTQ), and diffusion-weighted imaging (36 directions). Probabilistic tractography (using FreeSurfer's TRACULA) was used to assess diffusion metrics in the ILF.

Contrary to our hypothesis, there was no significant effect of diagnostic group on FA. In contrast, higher CTQ scores were significantly associated with lower FA in the ILF bilaterally. This association of maltreatment with lower FA remained statistically significant after controlling for diagnostic group, and it was significant for both criterion-A-type and noncriterion-A-type maltreatment categories.

This work contributes to a growing body of literature indicating that different forms of childhood maltreatment are associated with altered white matter microstructure in the ILF, an association pathway involved in integrating visual information from occipital regions with emotion processing functions of the anterior temporal lobe.