Anodal cerebellar tDCS modulates lower extremity pain perception

BACKGROUND: Previous studies have investigated the use of transcranial direct current stimulation (tDCS) for pain management. The studies investigating therapeutic neuromodulation with tDCS for lower extremity pain are scarce and inconclusive. OBJECTIVE: The aim of the present study was to analyze the effects of cerebellar tDCS on lower extremity sensory and pain thresholds in healthy volunteers. METHODS: This was a single-blind crossover repeated-measure study. Utilizing randomized conditions, we examined the effects of anodal, cathodal and sham stimulation of the right cerebellum in 14 healthy volunteers on sensory and pain thresholds which were induced in the right leg using electrical stimulation. tDCS intensity was 2 mA and the duration of the stimulation was 10 minutes. RESULTS: After anodal cerebellar stimulation the pain threshold of the ipsilateral leg was increased (p < 0.01). We could not detect any significant pain modulation with cathodal or sham stimulation (p > 0.05). Furthermore, no significant modulation of the sensory threshold was detected after anodal, cathodal or sham cerebellar tDCS (p > 0.05). CONCLUSIONS: Our results indicate that anodal cerebellar tDCS with a reference electrode positioned over the buccinator area modulates pain processing in the ipsilateral leg. Further investigation is required to evaluate possible application in chronic pain patients.