Effects of Transcranial Direct Current Stimulation in writing: a case report of deep agraphia

We present the case report of a 61-year-old male participant with chronic conduction aphasia and deep agraphia after ischemic stroke who received training on writing under dictation associated with transcranial direct current stimulation. The treatment consisted of five 50-minute dictation sessions with the application of 2 mA of anodal transcranial direct current stimulation for 20 minutes over the left occipitotemporal cortex. The participant improved his written production of pseudowords and regular low-frequency words, via the phonological route, in addition to a small improvement in the production of irregular words, via the lexical route. After training, there was also a small improvement in writing for untrained stimuli, suggesting generalization. In the assessment carried out 5 months after the end of the treatment, the benefit was maintained for stimuli processed via the phonological route. The results are promising given the severity and chronicity of the case and suggest that transcranial direct current stimulation associated with writing therapy represents a possible clinical alternative for patients with deep agraphia.