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Background: Cerebral specialization and inter-hemispheric cooperation are two of the most prominent functional architectures of the human brain. Their dysfunctions may be related to pathophysiological changes in patients with Parkinson's disease (PD), who are characterized by unbalanced onset and progression of motor symptoms.Objective: This study aimed to characterize the two intrinsic architectures of hemispheric functions in PD using resting-state functional magnetic resonance imaging.Methods: Seventy idiopathic PD patients and 70 age-, sex-, and education-matched healthy subjects were recruited. All participants underwent magnetic resonance image scanning and clinical evaluations. The cerebral specialization (Autonomy index, AI) and inter-hemispheric cooperation (Connectivity between Functionally Homotopic voxels, CFH) were calculated and compared between groups.Results: Compared with healthy controls, PD patients showed stronger AI in the left angular gyrus. Speci cally, this difference in specialization resulted from increased functional connectivity (FC) of the ipsilateral areas (e.g., the left prefrontal area), and decreased FC in the contralateral area (e.g., the right supramarginal gyrus). Imaging-cognitive correlation analysis indicated that these connectivity were positively related to the score of Montreal Cognitive Assessment in PD patients. CFH between the bilateral sensorimotor regions was signi cantly decreased in PD patients compared with controls. No signi cant correlation between CFH and cognitive scores was found in PD patients.Conclusions: This study illustrated a strong leftward specialization but weak inter-hemispheric coordination in PD patients. It provided new insights to further clarify the pathological mechanism of PD.

Objective: This study aimed to determine the minimal scanning duration of functional magnetic resonance imaging (fMRI) for producing individualized repetitive transcranial magnetic stimulation (rTMS) targets that are superior to the group-level targets.Materials and Methods: This study included 30 healthy subjects and 20 depressive patients with highsampled fMRI data (> 69 min). We computed suboptimal targets by gradually increasing the scanning duration beginning at 6 min. The target connectivity and spatial distance to the optimal target (based on the full-duration scanning data) were compared to an anatomically xed target from a group analysis (termed as the group target). These analyses were repeated for healthy subjects and depressive patients, as well as for target masks in the dorsal prefrontal cortex (DLPFC) and inferior parietal lobule (IPL).Results: As the scanning duration increased, the suboptimal targets gradually approached the optimal targets in the healthy subjects. Compared with the group targets, the suboptimal targets in the DLPFC showed higher connectivity strength after 10 min of data collection and shorter spatial distance after 40 min. Similar results were found in major depressive patients. In the IPL, the minimal scanning duration decreased to 6 and 8 min for connectivity strength and distance, respectively. Conclusion: These ndings provide an important reference for individualized target de nition in terms of scanning duration, which may standardize connectivity-based personalized studies.