Li X, et al. – This study was designed to examine the neural bases of expressive suppression (ES) and externally oriented thinking (EOT) and their association in females versus males in a Chinese college sample. The present structural magnetic resonance imaging study suggested that the ventromedial prefrontal cortex (vmPFC) could be the only neural base of ES and EOT and their association. Moreover, these results were sex–specific.

Methods

• An aggregate of one hundred forty two members (83 females) were selected, and they finished the ES subscale of the Emotion Regulation Questionnaire, 20-item Toronto Alexithymia Scale, and anatomical scanning.
• Voxel-based morphometry, region of interest, and whole brain analyses with peak-level significance (family-wise error corrected at p < .05) were conducted to explore the relationship of gray matter volume (GMV) variations with ES and EOT.
• A bootstrapping analysis was conducted to investigate the role of vmPFC volume in the ES-EOT association.

Results

• The results of this study showed that the ES scores were positively related to the GMV of the vmPFC in females and negatively linked to right dorsolateral PFC volume in males.
• Findings revealed that the EOT scores were positively correlated with the GMV of the vmPFC in females and supplementary motor area in males.
• vmPFC volume mediated the connection between ES and EOT.