Neural Substrates of Motor & Non-Motor Symptoms in PD

Brain regions were labeled as ipsilateral and contralateral to the more-affected body side. Correlation analysis between the functional connectivity across brain regions and the scores of various symptoms was performed to identify the neural connectivity correlates of each symptom.

Functional connectivity correlated with the MDS-UPDRS part I score.

The inferior orbito-frontal area in the ipsilateral hemisphere has substantial functional connectivity negatively correlated with the severity of non-motor symptoms. Other ipsilateral inferior frontal areas such as the pars triangularis and the anterior cingulate cortex also exhibit functional connectivity correlated with the severity of non-motor symptoms. (p<0.001) (Blue line: a functional connectivity negatively correlated with the MDS-UPDRS part I score; C: contralateral hemisphere & I: ipsilateral hemisphere.)