Transcranial direct current stimulation ameliorates tactile sensory deficit in multiple sclerosis

BACKGROUND: Deficit of tactile sensation in patients with MS is frequent and can be associated with interference with daily life activities. Transcranial direct current stimulation (tDCS) showed to increase tactile discrimination in healthy subjects. OBJECTIVE: In the present study, we investigated whether tDCS may be effective in ameliorating tactile sensory deficit in MS patients. METHODS: Patients received sham or real anodal tDCS of the somatosensory cortex for 5 consecutive days in a randomized, double blind, sham-controlled study. Discrimination thresholds of spatial tactile sensation were measured using the grating orientation task (GOT). As secondary outcomes we also measured subjective perception of tactile sensory deficit through a visual analog scale (VAS), quality of life and overall disability to evaluate the impact of the treatment on patients daily life. Evaluations were performed at baseline and during a 4-week follow-up period. RESULTS: Following anodal but not sham tDCS over the somatosensory cortex, there was a significant improvement of discriminatory thresholds at the GOT and increased VAS for sensation scores. Quality of life, and disability changes were not observed. CONCLUSION: Our results indicate that a five day course of anodal tDCS is able to ameliorate tactile sensory loss with long-lasting beneficial effects and could thus represent a therapeutic tool for the treatment of tactile sensory deficit in MS patients.