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Published on: May 23, 2011
Prefrontal tDCS Decreases Pain in Patients with Multiple Sclerosis.
Samar S Ayache1, Ulrich Palm2, Moussa A Chalah3
1EA 4391, Excitabilité Nerveuse et Thérapeutique, Université Paris-Est-CréteilCréteil, France; Service de Physiologie - Explorations Fonctionnelles, Hôpital Henri Mondor, Assistance Publique - Hôpitaux de ParisCréteil, France; Neurology Division, Lebanese American University Medical Center - Rizk HospitalBeirut, Lebanon.
Transcranial direct current stimulation (tDCS) effectively reduced neuropathic pain in multiple sclerosis (MS) patients. However, this neuromodulation technique did not improve attention, fatigue, or mood in the study cohort.
Area of Science:
- Neuroscience
- Neurology
- Medical Technology
Background:
- Transcranial direct current stimulation (tDCS) is an emerging therapeutic approach for enhancing brain functions.
- Prefrontal tDCS shows promise in improving cognitive function and alleviating symptoms like pain, fatigue, mood disturbances, and attention deficits, particularly relevant for multiple sclerosis (MS) patients.
Purpose of the Study:
- To investigate the effects of anodal tDCS over the left dorsolateral prefrontal cortex (DLPFC) on pain in MS patients.
- To assess the secondary outcomes of tDCS on attention, fatigue, and mood in the same patient group.
Main Methods:
- A randomized, sham-controlled, cross-over study involving 16 MS patients with chronic neuropathic pain.
- Patients received two blocks of anodal tDCS (active or sham), each with three daily sessions, separated by a 3-week interval.
- Pain was assessed using the Brief Pain Inventory (BPI) and Visual Analog Scale (VAS); attention was evaluated with neurophysiological parameters and the Attention Network Test (ANT); mood and fatigue were measured using various scales.
Main Results:
- Active tDCS demonstrated significant analgesic effects compared to sham, as indicated by VAS and BPI global scores.
- No significant improvements were observed in mood, fatigue, or attention following either active or sham tDCS blocks.
Conclusions:
- Anodal tDCS applied to the left DLPFC selectively ameliorates neuropathic pain in MS patients, potentially by modulating the emotional pain network.
- The lack of improvement in attention, mood, and fatigue may be due to the study's short protocol duration, small sample size, and cohort heterogeneity.
- Future research should explore different stimulation sites, montages, longer protocols, and neuroimaging techniques to elucidate tDCS mechanisms of action in MS.
