Demographics, neuropsychological test performance 1, and structural MRI volumes for the Control and Parkinson's groups.

1Neuropsychological testing was conducted in PD participants when they were taking their medication.2The total score (maximum = 30) is reported for the Mini-Mental State Exam [57].3T-scores are reported for the Trail Making Test [58].4Scaled scores are reported for the Digit Span and Spatial Span tests [59].5T-scores are reported for the Digit Vigilance Test [60].6T-scores for the dominant right hand are reported for the Finger Tapping Test [58].7Volumes are expressed as the percentage of estimated total intracranial volume (volume/eTIV).