TRANSCRANICAL DIRECT CURRENT STIMULATION IN POST-STROKE APHASIA REHABILITATION: BILATERAL VS UNILATERAL ONLINE STIMULATION

Abstract

Here we aim to evaluate the efficacy of repeated sessions of transcranial Direct Current Stimulation (tDCS) as additional treatment to standard behavioural rehabilitation in post-stroke aphasic patients comparing bilateral with unilateral left-sided and sham-tDCS. Background: Aphasia is the most common post-stroke cognitive disorder and it severely impacts activities of daily living and social interactions. tDCS recently showed good results in post-stroke aphasia rehabilitiation, even if no agreement at now exists about the stimulation parameters to employ to achieve the best rehabilitative outcome. Design/Methods: We enrolled twenty-two patients with single left-brain lesion at CT or MRI scan. The language disorder was investigated through selected subitems of Aachener Aphasie Test (AAT) administered before and after the treatment. Patients were randomly assigned to 3 treatments types: bilateral tDCS (7pts); unilateral tDCS (8pts); sham tDCS (7pts). Anode was placed on the left inferior frontal gyrus (IFG), while cathode was positioned on contralateral supraorbital area for unilateral-tDCS and on the right IFG for bilateral-tDCS. tDCS (1.5mA intensity for 20 min) was delivered during a picture naming task in daily sessions for two consecutive weeks (week-end free) for a total of 10 stimulation sessions. Results: Both dual and single-tDCS lead to significant improvements in outcome measures (AAT scores, in particular for naming subitems) as compared to baseline evaluation and sham-tDCS. Conclusions: tDCS showed to be an effective and safe tool in improving post-stroke patients' aphasic symptoms, with no difference between the two montages employed, even if these results have to be considered preliminary, since we are still widening our sample. IFG stimulation is worth to be further explored (wider samples and evaluation for optimal stimulation parameters) as additional rehabilitative tool for post stroke aphasic patients.