Altered Spontaneous Brain Activity in Somatic Symptom Disorder: A Resting-state fMRI Study

Abstract

Background: Somatic symptom disorders (SSDs) are common medical disorders characterized by various biological, social, and psychological pathogenic factors. Little is known about the neural correlations of SSD. Methods: In this study, we evaluated the dysfunction in 45 patients with SSD and in 43 controls by combining the regional homogeneity (ReHo) amplitudes of low-frequency fluctuation (ALFF) methods based on resting-state functional magnetic resonance imaging. Results: Compared to the controls, the patients with SSD exhibited significantly greater ReHo in the right cingulate gyrus and smaller ReHo in the right precuneus, left inferior and temporal gyrus extending to the left middle temporal gyrus and left parahippocampal gyrus, and right pons. The SSD patients showed higher ALFF values in the cingulate gyrus extending to the left medial frontal gyrus, right insula extending to the right inferior frontal gyrus, and left medial frontal gyrus extending to the left anterior cingulate cortex. Conclusions: These dysfunction areas seem to have a particular importance for the occurrence of SSD, which may result in dysfunction in self-relevant processes, emotional processing, multimodal integration, arousal, interoception, and body perception.