tDCS and Cognition in Adults With Multiple Sclerosis or Encephalitis

Transcranial Direct Current Stimulation and Cognition in Adults With Multiple Sclerosis or Encephalitis

This research is being done to determine whether transcranial direct current stimulation (tDCS) can improve certain mental abilities in individuals with multiple sclerosis (MS) or encephalitis. Participants will be asked to come in daily for two full weeks during which time participants will undergo cognitive testing and Magnetic Resonance Imaging (MRI) brain scans. In this research, a very weak electrical current is administered to the surface of the scalp while participants complete cognitive tasks. The investigators' aim is to find out whether tDCS will improve task performance in adults with multiple sclerosis or encephalitis.

Participants enrolled into this study may be asked to do the following: Come to the investigators' testing office at the Johns Hopkins Hospital where the tDCS equipment is located for 10 study visits. Grant permission for the researchers to view medical records associated with the participant's diagnosis of multiple sclerosis or encephalitis (if applicable) and general state of health. Complete a questionnaire and provide a health history in order to verify eligibility to participate and be able to safely undergo the experimental procedures. Complete several computerized, written, and/or aural tasks (i.e., saying words out loud) that assess different cognitive functions such as attention, memory, language, or processing speed. Wear electrodes that will be placed on the scalp with a large rubberized band. These electrodes will administer very weak electrical current (tDCS) for 30 minutes. Participate in several study conditions. The exact conditions and the order will be randomized. That is, the conditions and order will vary by chance (like the flip of a coin). Under some conditions, the participant might receive active stimulation (tDCS) and under other conditions, the participant might receive placebo (or sham) stimulation. Placebo stimulation is similar to active tDCS but lasts only a few seconds. However, all groups will wear the electrodes for the same length of time to prevent the participant from knowing whether participants are receiving active tDCS or sham stimulation. The study doctor and research staff will know which group the participant is in. Permission to audio and/or video-tape test sessions for later scoring and observation. These tapes will not be viewed by anyone not affiliated with the study without the participant's consent. Have structural, resting-state and functional Magnetic Resonance Imaging scans as a part of the study.

Transcranial direct current stimulation (tDCS) that is ramped up and ramped down providing the sensation of tDCS without delivering the full amount of tDCS first and then Anodal Stimulation second.

Transcranial direct current stimulation using Anodal stimulation first over the area of interest and then Sham Stimulation second.

Change in performance on an individual cognitive test measure raw score from the Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) battery tests (i.e. Paced Auditory Serial Addition Test scores). Change scores range from -120 to + 120. Positive change scores reflect improvement at the end of the intervention relative to baseline. Negative change scores reflect decline at the end of the intervention relative to baseline.

Change in Fatigue as Assessed by Multidimensional Fatigue Symptom Inventory 30-item Short Form (MFSI-SF) Total Scores

Fatigue was measured via changes in self-reported fatigue on the Multidimensional Fatigue Symptom Inventory 30-item short form (MFSI-SF) total score over the course of active and sham tDCS. Change scores range from -84 to + 84. Positive change values reflect increased symptom burden at the end of the intervention relative to baseline. Negative change scores reflect reduced symptom burden at the end of the intervention relative to baseline.

Inclusion Criteria: Diagnosis of multiple sclerosis or encephalitis Over the age of 18 Exclusion Criteria: A diagnosis of schizophrenia bipolar disorder Beck Depression Inventory-II scores over 20 Mini Mental Exam below 24 Any uncontrolled seizure disorder Any implanted metal device or hearing aids Use of medication shown to interact with tDCS effectiveness