Fig. 2: Cerebellar glucose metabolism differences in Parkinson’s disease subgroups and their correlation with cognitive and motor functions.

Violin plots (left) show differences in glucose metabolism in three significant brain regions across different PD subgroups. Regression curves (right) demonstrate the correlations between glucose metabolism and cognitive function (MoCA scores) or motor function (UPDRS-III scores). A Cerebellar lobule VI and MoCA scores: Violin plot: ANOVA revealed significant differences among the three groups (p < 0.001). Glucose metabolism in the PDD group was significantly higher than in the PD-NC group (p < 0.001) and the PD-MCI group (p = 0.005). The PD-MCI group also showed higher metabolism than the PD-NC group (p = 0.038).Regression curve: Glucose metabolism was significantly negatively correlated with MoCA scores (p < 0.001, r = −0.451). B Cerebellar lobule VIII and MoCA scores: Violin plot: ANOVA showed significant group differences (p < 0.001). The PDD group had higher glucose metabolism than the PD-NC group (p < 0.001) and the PD-MCI group (p = 0.013), and the PD-MCI group also had higher metabolism than the PD-NC group (p = 0.032). Regression curve: A significant negative correlation between glucose metabolism and MoCA scores was observed (p < 0.001, r = −0.428). C Cerebellar lobules IV and V and UPDRS-III scores: Violin plot: No significant differences were found between the TD and PIGD groups (p = 0.309). Regreon curve: Glucose metabolism was positively correlated with UPDRS-III scores (p < 0.001, r = 0.382). *p < 0.05, **p < 0.01. For comparisons among three groups, ANOVA followed by Bonferroni correction was used. For comparisons between the two groups, the Mann–Whitney test was applied.