Abnormal Activation and Connection in Middle Frontal Gyrus: A Potential Imaging Feature for Facial Synkinesis...

Patients with facial synkinesis (FS) comorbid depression may experience aggravated symptoms of perceived synkinesis and poorer recovery outcomes. Exploring imaging features associated with depressive symptoms could help us better understand disease conditions and formulate appropriate rehabilitation plans. Although abnormal activation in the middle frontal gyrus (MFG) has been reported in depression patients, whether it represents an imaging correlate of depressive symptoms in patients with FS is still unknown. Therefore, a total of 52 participants (20 normal controls [NCs], 32 patients) with both task and resting-state functional magnetic resonance imaging (rs-fMRI) data were included in this study. Comorbid depression was assessed with the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-V), and depressive symptom severity was measured with the Beck Depression Inventory-II (BDI-II). We investigated brain activation during motor tasks (smiling, blinking, and grinning). In addition, the seed-based functional connectivity (FC) between the MFG and other brain areas was calculated in the resting state. Additionally, we analyzed the associations between brain activity and clinical scale scores. The results revealed reduced activation in the sensorimotor and MFG during affected side movements across all tasks (voxel-level p < 0.05, cluster-level p < 0.05, Gaussian random field [GRF]-corrected). Moreover, seed-based FC between the MFG and emotion-related areas was increased (voxel-level p < 0.05, cluster-level p < 0.05, GRF-corrected), indicating impaired emotional networks in patients. Scores on the BDI-II were negatively associated with MFG activation during tasks (R = -0.318, p = 0.027) and positively associated with the FC of the MFG (R = 0.387, p = 0.029). Thus, the MFG activation and connectivity may represent an increased risk for elevated depressive symptoms in patients with FS, warranting further validation in future studies. Trial Registration: Chinese Clinical Trial Registry: ChiCTR1800014630.