CONICET | Buscador de Institutos y Recursos Humanos

Previous studies have shown that the application of non-invasive brain stimulation can potentially improve aspects of language training in patients with aphasia. The aim of the present study is to determine whether the application of transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex (DLPFC) combined with intensive individualized language training can improve lexical retrieval in patients with logopenic primary progressive aphasia (lvPPA). In the present double-blind, placebo-controlled crossover study, two patients (a 52-year-old woman and a 68-year-old-man) with diagnosis of lvPPA were included. Sham tDCS was applied for 6 consecutive days and then excitatory tDCS (AtDCS) was applied for another 6 days during of 20 minutes/day over left DLPFC. During the stimulation the patient received a semantic language training. The main outcome was the production of nouns and verbs in the picture description task and during spontaneous speech. Furthermore, naming in treated and untreated categories was analyzed. None of the patients was able to recognize real or sham stimulation. A statistically significant increase was obtained by comparing the number of verbs and nouns produced by both patients after training+AtDCS vs training+sham. Furthermore, we observed in one of the patients a statistically significant improvement in trained categories naming. These results demonstrate an improvement in the lexical activation of the trained categories and in verbs and nouns production, through the combination of AtDCS and semantic language therapy. Taking into account the lack of effective therapeutic alternatives, the present proof- of-principle study could be consider for a future randomized multicenter trial with a bigger design.