tDCS and Speech Therapy for Motor Speech Disorders Caused by FTLD Syndromes: a Feasibility Study

The investigators will test the feasibility of using transcranial direct current stimulation (tDCS) and speech therapy to treat participants with motor speech disorders caused by Frontotemporal Lobar Degeneration Pathology including nonfluent variant Primary Progressive Aphasia, Progressive Supranuclear Palsy, Corticobasal Syndrome, or behavioral variant Frontotemporal Dementia. The investigators will deliver transcranial direct current stimulation (tDCS) either in a clinic setting at the University of California San Francisco, or in patients' homes, via a consumer tDCS device and videoconferencing. Transcranial direct current stimulation (tDCS) is a neuromodulation technique that can enhance the benefits of speech therapy treatment. Participants will receive a dose of tDCS stimulation + speech therapy and a dose of sham tDCS + speech therapy in a randomized double blind crossover study performed either in the clinic or at home via videoconferencing. This study can be performed entirely remotely.