Effects of transcranial direct current stimulation in patients with non-fluent aphasia disorder

Aphasia, after stroke in the left hemisphere, is a common symptom. These patients often experience incomplete recovery despite intensive speech therapy. Direct electrical stimulation of the brain is a technique to stimulate the brain in patients with neurological and psychiatric diseases. The aim of this study was to investigate the effects of this stimulation on recovery of naming ability, working memory, and aphasia quotient and the lasting duration in patients with non-fluent aphasia. In this interventional study, 10 patients with after-stroke non-fluent aphasia were enrolled. Their aphasia quotient, working memory and naming ability scores were compared before and after sham and real treatments and two months after the real treatment. 10 sessions of 20-minutes sham electrical stimulation and 10 sessions of 20-minutes anodic and cathodic stimulation (2 mA) at the dorsal lateral perifrontal cortex was done for each patient. Data were analyzed using repeated-measures ANOVA and Friedman nonparametric tests. The ability of naming and working memory scores were increased significantly after treatment and two months after it compared with before study and after sham treatment (p<0.05 for all). There was no significant improvement in aphasia quotient. The transcranial direct current stimulation can sustain improvement in naming function and working memory in patients with non-fluent aphasia. It can be used in the rehabilitation program of these patients.