Transcranial Direct Current Stimulation for the Treatment of Primary Progressive Aphasia (P1.212)

OBJECTIVE: We investigated whether two weeks of daily anodal tDCS treatment would improve language abilities in PPA patients. We also asked whether these effects would be sustained for up to three months following stimulation. BACKGROUND: Primary Progressive Aphasia (PPA) is a neurobehavioral syndrome often seen in the setting of frontotemporal lobar degeneration (FTLD), which is characterized by gradual irreversible deterioration of language function. While effective treatments are lacking, limited preliminary data suggest that transcranial direct current stimulation (tDCS) may improve certain communication abilities in PPA patients. DESIGN/METHODS: Eight patients with PPA were recruited for the study, all of whom exhibited some disruption of verbal fluency. tDCS was applied at an intensity of 1.5mA for 20 minutes/day over two weeks (10 days). The anode was positioned over the left fronto-temporal region (F7) and the cathode was positioned over the left occipito-parietal region (O1). A battery of neuropsychological assessments was administered four times: at baseline, immediately following the 2-week stimulation period (post), and then at a 6-week and 12-week follow-up. RESULTS: We observed improvement in measures of naming, grammatical comprehension, repetition and sentence productivity at each of the post and follow-up sessions. For many subjects, these improvements seemed to gradually increase over the duration of the trial and peaked at the 12-week follow-up. Furthermore, the improvements among our patients were shown to be significantly greater when compared to severity-matched historical control patients on similar linguistic measures. CONCLUSIONS: Our results support the hypothesis that tDCS provides both a transient as well as a lasting improvement on some of the main language skills affected by PPA. This offers potential for the clinical implementation of tDCS in the treatment of PPA and other neurodegenerative conditions. Study Supported by: Disclosure: Dr. Gervits has nothing to disclose. Dr. Ash has nothing to disclose. Dr. Diloyan has nothing to disclose. Dr. Morgan has nothing to disclose. Dr. Coslett has nothing to disclose. Dr. Grossman has nothing to disclose. Dr. Hamilton has nothing to disclose.