The sex-related effect on copings to negative affect

Abstract

 Rumination is generally defined as a repetition of a theme in thoughts. Rumination has been consistently associated with psychopathologies. Among these psychopathologies, the relationship between depression and rumination is likely the most widely researched. Rumination was found able to predict onset of depression and duration of depressive symptoms. Rumination was also suggested to be a maladaptive coping to stress and distress, which enhance avoidant coping strategies and then further increase depression. Hence, understanding the neural basis of rumination would shed important insight into the mechanisms underpinning the regulation and dysregulation of emotion that would guide the development of cost-effective interventions. Study One was conducted to understand the sex-related differences in the rumination subtypes’ relationships with negative affect and avoidance. Thirty-six healthy participants (23 females, 13 males) were recruited in the community. We found a positive association between brooding and negative affect in both males and females. We also found, as hypothesized, a positive association between brooding and avoidance, and a negative association between reflective pondering and depression in females. A negative association between reflective pondering and avoidance was also found in males. However, reflective pondering was found to be positively associated with depression in males in this study. The findings suggest a gender difference in their emotional regulation. The brain structural correlation with this sex-related behavioral data was investigated through a voxel-based morphometry study. The sex-related difference of rumination subtypes and their relationship with negative affect, avoidance and brain volumes were explored. We found males having a larger gray matter volume over left anterior cingulate than females, and gray matter volume of this region was found to be associated with brooding in the literature. A significant interaction effect of gender and brooding was found over gray matter volume of left lateral parietal, while a significant interaction effect of gender and reflective pondering was found over gray matter volume of the several frontal regions. Consistent with the behavioral study findings, the left inferior temporal, left postcentral and right anterior cingulate were found to be associated with the significant associations between rumination and negative affect found in Study One. We also found the left inferior temporal and right precentral positively associated with brooding and behavioral-nonsocial avoidance in females. This was also found to be consistent with results from Study One.

In this study, the sex-related differences among rumination, negative affect and avoidant coping strategies were found to be correlated to the regional gray matter volumes. These findings do not only help us better understand the neural associates behind the sex-related behavioral differences often discussed and found in previous studies, they also give us further information and direction on the management plans of the emotional and avoidance problems associated with rumination.