Network hub changes in the pars opercularis indicate impaired inhibition in tic disorder patients

This study aimed to utilise graph theory to explore the functional brain networks in individuals with tic disorders and to investigate resting-state functional connectivity changes in critical brain regions associated with tic disorders.

Participants comprised individuals with tic disorders and age-matched healthy controls, ranging from 6 to 18 years old, all recruited from Korea University Guro Hospital. We ensured a medication-naïve cohort by excluding participants exposed to psychotropic medications for at least three weeks prior to the study. Data included structural and resting-state functional MRI scans, analysed with the CONN-fMRI Functional Connectivity toolbox v20b. The analysis included 22 patients (18 males, 4 females) and 26 controls (14 males, 12 females).

Significantly increased global efficiency was observed in the left inferior frontal gyrus pars opercularis among tic disorder patients compared to controls. Furthermore, this region displayed enhanced resting-state functional connectivity with its right counterpart in patients versus controls.

The inferior frontal gyrus pars opercularis, known for its inhibitory role, may reflect adaptive functional adjustments in response to tic symptoms. Increased hubness of the inferior frontal gyrus pars opercularis possibly represents functional adjustments in response to tic symptoms. The identified brain region with increased efficiency and connectivity presents a promising avenue for further research into tic expression and control mechanisms.