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

Summary

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.

Conditions

• Cognitive Impairment
• Multiple Sclerosis

Interventions

DEVICE

Experimental group (EG) performing Anodal-tDCS (A-tDCS) and VR

Patients in the EG group will undergo a simultaneous A-tDCS over the left DLFPC. The tDCS will be delivered by a battery-driven, constant current simulator, two holding bags of plant cellulose (7x5 cm) and two electrodes of conductive silicone. The active (anodal) electrode will be placed by means of a cap on the scalp overlying the left DLPFC (46 Brodmann Area). The reference electrode will be located over the right shoulder. The choice of the left DLPFC as the site of stimulation relies upon the evidence that this region has a critical role in the "top-down" control of the task-relevant stimuli processing (Miller 2001).The DLPFC contributes to increase cognitive control through its connections with the anterior cingulate cortex and has been shown to enhance working memory and executive function. During the cognitive training (on-line procedure), A-tDCS (current of 1,5 mA) will be delivered for 20 minutes, while maintaining the current density (0.06 mA/cm2) below the safety limits.

DEVICE

Sham Comparator: Control group (CG) performing sham-tDCS (S-tCDS) and VR

CG will receive a S-tDCS over the DLPFC. In the S-tDCS session, the current will be turned off 30 sec after the beginning of the stimulation and turned on for the last 30 sec. By doing this, the patient feels an itching sensation below the electrodes at the beginning and at the end of stimulation, making this condition indistinguishable from the real A-tDCS stimulation. Doing this, all the subjects will be blinded on the type of stimulation. As well as in the EG, CG performs cognitive training including motor and cognitive exergames that incorporate enjoyment, technology, and health care.

Sponsors & Collaborators

• Italian Multiple Sclerosis Foundation

  collaborator OTHER

• Ospedale Policlinico San Martino

  lead OTHER

Principal Investigators

• Laura Mori, MD, PhD · Ospedale Policlinico San Martino IRCCS

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

65 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2024-09-02

Primary Completion

2026-01-31

Completion

2026-01-31

Countries

• Italy

Study Locations