Remotely Supervised Transcranial Direct Current Stimulation (tDCS) for Primary Progressive Aphasia (PPA)

Remotely Supervised Transcranial Direct Current Stimulation (tDCS) for Primary Progressive Aphasia (PPA)

The purpose of this study is to establish the feasibility of a program of remotely supervised transcranial direct current stimulation (RS-tDCS) paired with language skills practice for people living with the semantic or logopenic variants of primary progressive aphasia (PPA). There are currently no established standard-of-care treatments for PPA. This study will evaluate whether RS-tDCS combined with language skills practice is a feasible study design for individuals with PPA.

Inclusion Criteria:

1. Primary progressive aphasia diagnosis (logopenic or semantic variant)
2. Peabody Picture Vocabulary Test (PPVT) score < -1.0 SD, serving as a literacy proxy for premorbid cognitive ability and ensuring English language fluency sufficient for participation in the study procedures.
3. WAIS-IV Matrix Reasoning T score < 20, serving as an index of current general cognitive functioning to exclude those with severe cognitive impairment
4. Stable and continuous access to internet service, email (WiFi "hotspot" to be provided if needed)
5. Fluent in English language (due to outcomes validated in English versions only)

Exclusion Criteria:

1. Disorder other than PPA known to cause language dysfunction
2. Diagnosis of nonfluent/agrammatic subtype of primary progressive aphasia
3. History of traumatic brain injury
4. Uncontrolled seizure disorder and/or recent (<5 years) history of seizure
5. Metal implants in the head or neck
6. Any skin disorder or skin sensitive area near stimulation locations
7. Pregnant or breastfeeding