Effects of tDCS and Cognitive Rehabilitation on Cognition and Neural Plasticity in MS Patients

NCT07160218 | Completed DMC

• 1 other identifier: IR.SBMU.PHNS.REC.1402.121
• Study Type: interventional
• Target: 45
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to evaluate whether transcranial direct current stimulation (tDCS) and cognitive rehabilitation can improve cognitive functions and neuronal plasticity in patients with multiple sclerosis (MS). The participant population consists of MS patients (both sexes, adults), who commonly experience cognitive impairment in addition to physical and psychological symptoms. The main questions it aims to answer are: Does tDCS applied over the left dorsolateral prefrontal cortex improve cognitive abilities in MS patients? Does the combination of tDCS and cognitive rehabilitation enhance neuroplasticity, as measured by DTI, BDNF levels, and acetylcholinesterase activity?

Conditions

Multiple Sclerosis

Outcome Measures

Primary Outcomes (6)

• Change in verbal memory performance measured by California Verbal Learning Test-II (CVLT-II)

  The CVLT-II assesses verbal learning and memory through a word recall task. Scores include total recall, short-delay recall, and long-delay recall. Assessments will be conducted at baseline and after 4 weeks of intervention.

  Baseline and immediately after 10 intervention sessions

• Change in attention performance measured by Integrated Visual and Auditory Continuous Performance Test (IVA-2)

  The IVA-2 evaluates visual and auditory attention and response control. Scores include full-scale attention quotient, visual attention, auditory attention, and response control. Assessments will be conducted at baseline and post-intervention to assess changes in attention performance

  Baseline and immediately after 10 intervention sessions

• Change in visuospatial memory performance measured by Rey-Osterrieth Complex Figure Test

  The Rey-Osterrieth Complex Figure Test evaluates visuospatial constructional ability and memory. Participants copy a complex figure (copy trial) and then reproduce it from memory immediately and after a delay. Assessments will be conducted at baseline and after completion of the tDCS intervention to assess changes in visuospatial memory performance.

  Baseline and immediately after 10 intervention sessions

• Change in serum BDNF levels (ng/mL)

  Serum brain-derived neurotrophic factor (BDNF) concentration will be measured using an enzyme-linked immunosorbent assay (ELISA). Blood samples will be collected at baseline and after completion of the tDCS intervention. Changes in BDNF levels will be analyzed to assess neuroplasticity.

  Baseline and immediately after 10 intervention sessions

• Change in white matter integrity measured by Diffusion Tensor Imaging (DTI)

  White matter integrity will be assessed using DTI MRI scans. Primary metrics include Fractional Anisotropy (FA) and Mean Diffusivity (MD) in predefined brain regions. Scans will be performed at baseline and after completion of the tDCS intervention to evaluate neuroplasticity-related changes

  Baseline and immediately after 10 intervention sessions

• Change in acetylcholinesterase (AChE) activity in blood (U/mL)

  Acetylcholinesterase activity will be measured in blood samples using a spectrophotometric enzymatic assay. Samples will be collected at baseline and after completion of the tDCS intervention. Changes in AChE activity will be analyzed to assess cholinergic system function and neuroplasticity.

  Baseline and immediately after 10 intervention sessions

Study Arms (3)

tDCS

EXPERIMENTAL

A 30-minute tDCS session with the cathode placed over the left dorsolateral prefrontal cortex (DLPFC)

Device: tDCS

tDCS+Cognitive training

EXPERIMENTAL

A 30-minute tDCS session with the cathode over the left DLPFC combined with computer-based cognitive rehabilitation training

Device: tDCS; Device: Cognitive Rehabilitation

Sham tDCS

SHAM COMPARATOR

Sham stimulation applied over the left DLPFC, mimicking the sensation of tDCS without delivering active current

Device: Sham tDCS

Interventions

tDCS DEVICE

A 30-minute tDCS session with the cathode placed over the left dorsolateral prefrontal cortex (DLPFC), delivered in 10 sessions over 2 weeks. This protocol targets cognitive improvement in MS patients

tDCS; tDCS+Cognitive training

Cognitive Rehabilitation DEVICE

computer-based cognitive rehabilitation exercises. Conducted in 10 sessions over 2 weeks to enhance attention, memory, and neuroplasticity in MS patients.

tDCS+Cognitive training

Sham tDCS DEVICE

Sham stimulation applied over the left DLPFC for 30 minutes, mimicking the sensation of tDCS without delivering active current, over 10 sessions, used as control to blind participants to the intervention

Sham tDCS

Eligibility Criteria

• Age: 20 Years - 50 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Age between 20 and 50 years.
• Diagnosed with relapsing-remitting multiple sclerosis (RRMS).
• Mild disability, defined as EDSS \< 5.
• Patients who attended the neurology clinic and are willing to participate.

You may not qualify if:

• Presence of psychiatric disorders requiring treatment with neuroleptics.
• History of seizures.
• Left-handed individuals.
• Recent MS relapse requiring steroid treatment.
• Pregnant women.
• History of brain surgery or presence of intracranial clips.

Sponsors & Collaborators

• Shahid Beheshti University of Medical Sciences: lead

Study Sites (1)

Shahid Beheshti University of Medical Science

Tehran, Iran

Location

MeSH Terms

Conditions

Multiple Sclerosis

Interventions

Transcranial Direct Current Stimulation; Cognitive Training

Condition Hierarchy (Ancestors)

Demyelinating Autoimmune Diseases, CNS; Autoimmune Diseases of the Nervous System; Nervous System Diseases; Demyelinating Diseases; Autoimmune Diseases; Immune System Diseases

Intervention Hierarchy (Ancestors)

Electric Stimulation Therapy; Therapeutics; Convulsive Therapy; Psychiatric Somatic Therapies; Behavioral Disciplines and Activities; Electroshock; Psychological Techniques; Neurological Rehabilitation; Rehabilitation; Aftercare; Continuity of Patient Care; Patient Care; Health Services; Health Care Facilities Workforce and Services

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor of Neurology

Study Record Dates

• First Submitted: August 26, 2025
• First Posted: September 8, 2025
• Study Start: January 2, 2024
• Primary Completion: August 1, 2025
• Study Completion: August 15, 2025
• Last Updated: September 8, 2025

Record last verified: 2025-09

Locations

IR (1)