Transcranial direct current stimulation plus concurrent activity may influence task prioritization during walking in people with Parkinson’s disease – initial findings

Abstract

Introduction:

Walking for people with Parkinson’s disease (PD) degrades during motor–cognitive interplay (ie, dual-task conditions). Current management of PD improves motor symptoms but inadequately addresses cognitive function, indicating a necessity for novel interventions. In this pilot study, we examined bi-hemisphere transcranial direct current stimulation (tDCS) with concurrent activity and dual-task walking in people with PD.

Methods:

Participants received 3 sessions (tDCS_sitting, tDCS_bike, tDCS_Wii) of bilateral tDCS (dorsolateral prefrontal cortex; left = anode, right = cathode) at 2 mA and 1 sham session (tDCS_sham). Sessions were randomized, single-blinded, and performed during medication “ON” times separated by 7±2 days. Following each session, participants performed Timed Up and Go (TUG) single, dual-task conditions (TUG_alone, TUG_motor, TUG_cognitive).

Results:

Sixteen participants with PD completed this study (mean age=68.13±9.76 years, Unified Parkinson’s Disease Rating Scale mean=40.31±18.27, Repeatable Battery for the Assessment of Neuropsychological Status mean=84.13 [13th percentile]). No differences were observed for TUG conditions between tDCS sessions. Dual task cost for TUG_motor, 14.73% (tDCS_Sitting), 17.78% (tDCS_Bike), 15.97% (tDCS_Wii)), 19.02% (tDCS_Sham); for TUG_cognitive (walking), 20.01% (tDCS_Sitting), 18.7% (tDCS_Bike), 31.18% (tDCS_Wii), 20.01% (tDCS_Sham); for TUG_cognitive (cognitive), 33.72% (tDCS_Sitting), 14.99% (tDCS_Bike), 4.42% (tDCS_Wii), 19.11% (tDCS_sham).

Conclusion:

Our bi-hemisphere tDCS paired with concurrent activities did not lessen dual-task cost in participants with PD but appeared to influence task prioritization. Further investigation with a larger sample size is warranted.

Keywords::

• dual task interference
• gait
• executive function
• non-invasive brain stimulation
• novel task
• motor-cognitive interplay

Author contributions

CC, CS, JM: conception and design. CC, CS, JM: data acquisition. CC, CS, SA: data analysis. CC, CS, SA, JM: interpretation. CC, CS, SA, JM: manuscript drafting or critique. CC, CS, SA, JM: manuscript, approval of final version. All authors contributed toward data analysis, drafting and revising the paper, gave final approval of the version to be published, and agree to be accountable for all aspects of the work.

Disclosure

The authors report no conflicts of interest in this work.