فصلنامه روانشناسی شناختی

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Multiple sclerosis is a de-myelinating inflammatory condition of the central nervous system that is often thought of as an autoimmune disorder. These patients suffer from extensive cognitive impairments such as poor attention and concentration and memory and processing speed; Therefore, the aim of this study was to investigate the anodic effect of direct cortical electrical stimulation (tDCS) on sustained attention performance in patients with multiple sclerosis (MS) in a pretest-posttest design with a control group. For this purpose, 32 patients with MS were selected using available sampling method and randomly assigned to experimental and control groups. The intervention consisted of 10 sessions of direct electrical stimulation during which patients were divided into two groups, one group received real stimulation and the other group received sham stimulation or sham. The research instruments were the use of RTI and RVP subtests in CANTAB test. Data analysis was performed based on independent and dependent t-test to compare pre-test and post-test scores in experimental and control groups. The results showed an improvement in sustained attention and processing speed in the experimental group at a significant level of 0.05. Therefore, we conclude that transcranial electrical stimulation of the brain improves sustained attention deficit and speed of response in patients with MS.