Impact of Anodal tDCS and Virtual Reality on Cognitive Dysfunction in Patients With Multiple Sclerosis

Cognitive impairment (CI) affects a large amount of patients with Multiple Sclerosis (PwMS) even in the early stages of the disease, increasing the perception of fatigue and compromising the quality of life. Different restorative interventions have been tried in order to alleviate CI, but with limited efficacy . Transcranial direct current stimulation (tDCS), represents a very promising alternative, or add-on, to the traditional rehabilitative approaches in MS. Notably, other novel technologies, such as Virtual Reality (VR) and Exergame, are emerging as a reinforcing tool to the rehabilitative treatment of PwMS. tDCS and VR can be combined in protocols aimed at achieving a better therapeutic benefit across different neurological diseases (Cassani 2020). The aim of our project is to explore the potential benefits of the simultaneous application of AtDCS and VR in the rehabilitation of cognitive impairment of PwMS. The VR approach will be implemented with a non-immersive VR system (exergames). As a secondary outcome, we wish to verify whether our protocol may extend its benefits over 6 months. Eighty PwMs with CI will be consecutively enrolled. Their cognitive status will be assessed by a neuropsychological battery: the Brief International Cognitive Assessment for MS and the Paced Auditory Serial Addition Test. To be considered cognitively impaired one has to abnormally score on at least two tests. Forty patients will be randomized to the experimental group (EG) or to the control group (CG). All the patients will undergo rehabilitative treatment with exergame (10 sessions for two consecutive weeks, 5 days per week). The EG patients will undergo a concurrent A-tDCS over the left dorsolateral prefrontal cortex, while the CG will receive a sham stimulation (S-tDCS). The patients will be evaluated at baseline, at the end of the treatment, one month and six months later. The statistical analyses will be done using repeated-measures ANOVA. Expected results: we hypothesize that the cognitive performances of both EG and CG groups will show an improvement in the cognitive performances. We will expect, however, a significative difference between the two groups, with patients in the EG group demonstrating better results than the CG group. Finally, we hypothesize the beneficial effects in EG patients will last at least one month after the end of the experiment.