Demographics table for the healthy control (N = 21), Alzheimer’s disease (AD; N = 18), dementia with Lewy bodies (DLB; N = 17) and Parkinson’s disease dementia (PDD; N = 17) groups that were used for our analysis. L-DOPA = levo-dopa, LED = L-DOPA equivalent dose, AChEIs = acetylcholinesterase inhibitors, MMSE = Mini mental state examination, CAF = Clinician’s assessment of fluctuations scale, UPDRS = Unified Parkinson’s disease rating scale, NPI = Neuropsychiatric inventory total score. Although it is not shown in the table, 1 PDD patient (5.9%) was on memantine.