Feasibility and potential effects of mental imagery training on subjective cognitive function and brain connectivity in people with Parkinson’s disease: A randomized pilot trial

Cognitive impairment is a debilitating problem in Parkinson's disease (PD) with no effective treatment. This pilot randomized controlled trial (ClinicalTrials.gov identifier NCT05495997) tested the feasibility of a personalized mental imagery (MI) intervention focusing on goal-directed activities of daily living in people with PD. We screened 51 and randomized 30 nondemented people with PD. During the six-week training period delivered remotely, PD-MI group practiced MI and PD-Control group received psychoeducation on cognitive health in PD. The primary objective was testing protocol feasibility. We also collected cognitive and functional MRI data at baseline, six weeks, and 18 weeks, specifically, to assess the feasibility of using the Neuro-QoL Cognitive Function (CF) self-report survey and brain functional connectivity as potential efficacy outcome measures in a future definitive trial. Retention and participant compliance with study procedures were 100% during six weeks. There were (1) group differences in the Neuro-QoL-CF T-scores at six and 18 weeks, driven by a reduction in the control group scores, (2) stronger frontoparietal connectivity at six weeks, and (3) weaker visuospatial-motor connectivity at 18 weeks during MI tasks in the PD-MI compared to the PD-Control group. These cognitive and brain connectivity changes should be tested in a fully powered trial.