Regional homogeneity of intrinsic brain activity related to the main alexithymia dimensions

BACKGROUND: Alexithymia is a multidimensional personality construct. OBJECTIVE: This study aims to investigate the neuronal correlates of each alexithymia dimension by examining the regional homogeneity (ReHo) of intrinsic brain activity in a resting situation. METHODS: From university freshmen, students with alexithymia and non-alexithymia were recruited. Their alexithymic traits were assessed using the Toronto Alexithymia Scale-20. The ReHo was examined using a resting-state functional MRI approach. RESULTS: This study suggests significant group differences in ReHo in multiple brain regions distributed in the frontal lobe, parietal lobe, temporal lobe, occipital lobe and insular cortex. However, only the ReHo in the insula was positively associated with difficulty identifying feelings, a main dimension of alexithymia. The ReHo in the lingual gyrus, precentral gyrus and postcentral gyrus was positively associated with difficulty describing feelings in participants with alexithymia. Lastly, the ReHo in the right dorsomedial prefrontal cortex (DMPFC_R) was negatively related to the externally oriented thinking style of participants with alexithymia. CONCLUSION: In conclusion, these results suggest that the main dimensions of alexithymia are correlated with specific brain regions’ function, and the role of the insula, lingual gyrus, precentral gyrus, postcentral gyrus and DMPFC_R in the neuropathology of alexithymia should be further investigated.