Reduced segregation and integration of structural brain network associated with sympathetic and dorsal penile nerve...

Recent neuroimaging studies have indicated that some brain areas are involved in the sexual behavior process. Pre-mature ejaculation patients exhibit altered brain activation and abnormal cortical structures. However, there has been no research evaluating the topological organization of structural brain network in anejaculation (AE).

We employed diffusion tensor imaging data and graph theory to examine the whole-brain structural networks among 16 AE patients and 23 healthy controls. In addition, the results of sexual function assessment were also obtained from each patient for symptom assessment. Moreover, the relationships between these clinical features and the altered topological characteristics of AE patients were also explored.

Decreased clustering coefficient was found in the right amygdala, inferior temporal gyrus, and left pallidum of AE. AE also showed increased path length in the right post-central gyrus, supramarginal gyrus, putamen, pallidum and left heschl gyrus, temporal pole (superior temporal gyrus); however, these altered brain regions showed no significant differences after false discovery rate correction. Moreover, the path length between subcortical and frontal regions was increased in AE. In addition, negative correlations were found between the altered nodal parameters and the amplitudes of somatosensory evoked potentials of dorsal nerve, sympathetic skin response located in the penis.

Together, our results suggest that AE was associated with disruptions in the topological organization of structural brain networks. The decreased clustering coefficient in temporal and subcortical regions and the increased path length between subcortical and frontal regions may contribute to AE. These findings provide new insights into the pathophysiological mechanisms of AE.