Non-invasive Brain Stimulation to Improve Memory in Multiple Sclerosis

Using two treatment arms, the study will examine improvement of verbal retrieval and other cognitive deficits associated with multiple sclerosis by comparing (1) 1 milliamp of High Definition transcranial Direct Current Stimulation (HDtDCS) active treatment applied to left inferior frontal gyrus for 20 minutes over 10 sessions to (2) sham HDtDCS following the same schedule. Additionally, after completing the initial active or sham treatment and immediate and 2-month follow-up testing sessions, participants will complete a second set of 10 sessions where they will switch conditions (i.e., those who received active stimulation will be switched to sham, and vice versa), and the will be re-evaluated at immediate and 2-month follow-up testing sessions. Patients with multiple sclerosis and observed cognitive deficits will be randomly assigned to one of the two treatment arms (and re-assigned for the second round of intervention, as described above). Primary outcome verbal retrieval measures, secondary neuropsychological and electroencephalography (EEG) measures, and prescreening assessments for study concussion history and contraindications for treatment will be collected prior to being assigned to a treatment arm (i.e., baseline). Primary outcome verbal retrieval measures and secondary neuropsychological and electroencephalography (EEG) measures will be collected at baseline and two times following each treatment competition (i.e., immediate and 2-months).