Cognitive Training and Transcranial Direct Current Stimulation for Mild Cognitive Impairment in Parkinson's Disease: A Randomized Controlled Trial

Blake J Lawrence; Natalie Gasson; Andrew R Johnson; Leon Booth; Andrea M Loftus

doi:10.1155/2018/4318475

Cognitive Training and Transcranial Direct Current Stimulation for Mild Cognitive Impairment in Parkinson's Disease: A Randomized Controlled Trial

Parkinsons Dis. 2018 Mar 26:2018:4318475. doi: 10.1155/2018/4318475. eCollection 2018.

Authors

Blake J Lawrence^{1

2

3

4}, Natalie Gasson^{1

2}, Andrew R Johnson^{1

2}, Leon Booth^{1

2}, Andrea M Loftus^{1

2}

Affiliations

¹ Curtin Neuroscience Laboratory, School of Psychology and Speech Pathology, Curtin University, Bentley, WA 6102, Australia.
² ParkC Collaborative Research Group, Curtin University, Bentley, WA 6102, Australia.
³ Ear Science Institute Australia, Subiaco, WA, Australia.
⁴ Ear Sciences Centre, School of Surgery, The University of Western Australia, Crawley, WA, Australia.

Abstract

This study examined whether standard cognitive training, tailored cognitive training, transcranial direct current stimulation (tDCS), standard cognitive training + tDCS, or tailored cognitive training + tDCS improved cognitive function and functional outcomes in participants with PD and mild cognitive impairment (PD-MCI). Forty-two participants with PD-MCI were randomized to one of six groups: (1) standard cognitive training, (2) tailored cognitive training, (3) tDCS, (4) standard cognitive training + tDCS, (5) tailored cognitive training + tDCS, or (6) a control group. Interventions lasted 4 weeks, with cognitive and functional outcomes measured at baseline, post-intervention, and follow-up. The trial was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR: 12614001039673). While controlling for moderator variables, Generalized Linear Mixed Models (GLMMs) showed that when compared to the control group, the intervention groups demonstrated variable statistically significant improvements across executive function, attention/working memory, memory, language, activities of daily living (ADL), and quality of life (QOL; Hedge's g range = 0.01 to 1.75). More outcomes improved for the groups that received standard or tailored cognitive training combined with tDCS. Participants with PD-MCI receiving cognitive training (standard or tailored) or tDCS demonstrated significant improvements on cognitive and functional outcomes, and combining these interventions provided greater therapeutic effects.