Home-based tDCS in Frontotemporal Dementia or Alzheimer's Disease

Remote Home-based Electrical Stimulation (tDCS) in Primary Progressive Aphasia (With Frontotemporal Dementia or Alzheimer's Pathology) and Mild Cognitive Impairment/Alzheimer's.

The primary objective of this research is to evaluate the effects of non-invasive brain stimulation and computerized cognitive training on executive functioning in individuals with Primary Progressive Aphasia (PPA), mild cognitive impairment (MCI), or dementia. In this study, investigators will use transcranial direct current stimulation (tDCS) to stimulate the left dorsolateral prefrontal cortex (DLPFC). Previous studies have demonstrated that tDCS over the DLPFC led to improvements in attention deficit caused by stroke, Parkinson's Disease, and major depression as well as language deficits caused by neurodegenerative conditions such as primary progressive aphasia or mild cognitive impairment. The investigators seek to expand on this literature by investigating how anodal tDCS paired with and without cognitive training will impact executive functioning in PPA with Frontotemporal Dementia or Alzheimer's Disease pathology and Mild Cognitive Impairment/Alzheimer's Disease (e.g. shifting, updating, monitoring, and manipulation).

In this within-subject cross-over protocol, all participants will receive both, cognitive training and brain stimulation tDCS. Participants will be randomly assigned to begin with either cognitive training and brain stimulation (dual therapy) or just brain stimulation (monotherapy) and will receive the complementary therapy program in the second round of treatment. During each period of therapy, participants will receive 50 treatment sessions over the course of approximately 10 weeks. The computerized cognitive training and brain stimulation will both be preprogrammed to be done at home by the participant.

Inclusion Criteria:

• Must be clinically diagnosed with PPA, fronto-temporal dementia (FTD), MCI or mild Alzheimer's disease (AD). Diagnosis will be based on neuropsychological testing, language testing (most commonly the Western Aphasia Battery), MRI, and clinical assessment.
• Must be right-handed.
• Must be proficient in English.
• Must have a minimum high-school education.

Exclusion Criteria:

• Uncorrected visual or hearing impairment by self-report.
• Stroke/other premorbid neurological disorder affecting the brain.
• Any other developmental language-based learning disorder other than PPA.
• Inability to follow directions for baseline tasks.
• Pre-existing psychiatric disorders such as behavioral disturbances, severe depression, and schizophrenia that do not allow them to comply or follow the study schedule and requirements such as repeated evaluation and therapy will be excluded.

Exclusion Criteria for MRI participation:

• Severe claustrophobia.
• Cardiac pacemakers or ferromagnetic implants.
• Pregnant women.