tDCS as Treatment for Motor Function

Transcranial Direct Current Stimulation as a Treatment for Motor Function in Participants Living With Progressive Supranuclear Palsy, Corticalbasal Syndrome Degeneration, or Parkinson's Disease

Previous preliminary results are sufficiently impressive to suggest that tDCS stimulation does have the potential to improve motor function when that ability is trained during stimulation. In the proposed study, the investigation will assess whether walking sessions combined with tDCS lead to improvements in motor function: gait, articulation, eye gaze, and motor dexterity. In addition, the investigators wish to examine if such results can be replicated in people with other conditions, such as cortical basal syndrome, and Parkinson's disease.

Previous preliminary results are sufficiently impressive to suggest that tDCS stimulation does have the potential to improve motor function when that ability is trained during stimulation. In the proposed study, the investigators will assess whether walking sessions combined with tDCS lead to improvements in motor function: gait, articulation, eye gaze, and motor dexterity. In addition, the investigators wish to examine if such results can be replicated in people with other conditions, such as cortical basal syndrome, and Parkinson's disease. The rationale for including people living with these conditions is the overlap in motor and cortical network dysfunction observed across these disorders. All three conditions involve impairment of motor initiation, gait, coordination, and executive motor control due to degeneration in frontal-subcortical pathways. This extension will also allow for comparison of stimulation responsiveness across related diagnostic groups and provide insight into disease-specific factors influencing motor recovery potential.

Previous tDCS studies have found significant results with sample sizes between 10-20 participants for a two-round study comparing training sessions with real tDCS versus sessions done without tDCS. However, the investigators plan to recruit 30 participants living with each condition as this will allow us to examine results per group, but also how the individual groups compare.

Inclusion Criteria:

- 1. Participants must be able to walk unassisted, or with the assistance of a walker or cane, and be individuals who walk daily.

2. Participants should have a sufficient level of English to be able to express themselves verbally, be able to read and follow instructions.

Exclusion Criteria:

• 3. Individuals with metal implants within the brain such as shunts will be excluded.