Magnetic Stimulation May Improve Memory in Multiple Sclerosis

Working memory was improved in patients with MS who underwent repetitive transcranial magnetic stimulation.

Magnetic stimulation of the brain may help patients with multiple sclerosis (MS) improve memory by rebuilding the brain’s network, according to a study published by the Journal of Neurology, Neurosurgery, and Psychiatry.

Repetitive transcranial magnet stimulation (rTMS) is an FDA-approved treatment for patients with major depression. For this therapy, physicians place a device on the patient’s scalp that transmits electromagnet impulses to certain areas of the brain.

Since rTMS targets specific areas of the brain, patients may experience less side effects compared with other brain stimulation techniques. Scalp discomfort, headaches, brief lightheadedness, and muscle contractions are common side effects. The procedure lasts for 30 to 60 minutes, and patients experience a slight tapping on their head during rTMS.

Previous studies have found that rTMS may also improve symptoms of depression among patients with MS.

Researchers in the current study defined working memory as the memory needed to perform day-to-day tasks, such as simple calculations or thinking through a problem.

Included in the study were 17 patients with MS, and 11 control patients who displayed no signs of memory dysfunction. Patients received rTMS and a lower intensity version of rTMS, which was referred to as sham-rTMS, according to the study.

All patients underwent imaging and neuropsychological tests to evaluate their memory before and after receiving the designated treatments. Patients then received 3 sessions of treatment — baseline, real-rTMS, and sham-rTMS.

The investigators assessed brain activity as participants completed a working memory task through a magnetic resonance scanner, according to the study. Doing so allowed the researchers to observe the brain function in real time while the patient was using their memory.

While there were no observable differences between the groups at baseline, the researchers found that treatment with real-rTMS improved brain function. The researchers also discovered improvements in working memory, brain activity, and connectivity between the prefrontal cortex and other areas of the brain, according to the study.

These results were not seen in control patients, and the authors reported that sham-rTMS did not elicit similar beneficial effects.

The findings suggest that rTMS changes the brain efficacy among patients with MS, and leads to healthier function. However, the study authors warn that their study is limited by the size of their study, and the patients’ memory function was not clear.

Additional studies are needed to determine if rTMS is a safe and effective way to improve cognitive function in patients with MS, the study concluded.