Stroke Patients Benefit from Transcranial Magnetic Stimulation

Newswise — High frequency repetitive transcranial magnetic stimulation (rTMS) shows promise in improving motor functioning of stroke patients suggests a new study. The study conducted by Korean researchers was reported today at the annual meeting of the American Association of Electrodiagnostic Medicine in Savannah, Georgia.

Stroke patients face a major hurdle in regaining use of arms, legs, and other muscle groups paralyzed by stroke. Because strokes often involve damage to areas of the brain that control movement or motor skills, the search for effective rehabilitation techniques has focused on non-invasive means of restoring and enhancing brain functioning.

Historically, interventions made on the brain have been fairly drastic—from holes bored in the skull by primitive healers to the drugs, electrical treatments and psychosurgery of more recent times. While these approaches have combined to alleviate or prevent many conditions that meant either death or chronic misery for the sufferer, they have often carried enormous risk or drastic side effects due to the severity of the interventions used.

Transcranial magnetic stimulation (TMS) is one very promising avenue for influencing the living brain that has emerged in the last decade. It is based on the use of pulsed magnetic fields. Fields are generated by passing current pulses through a conducting coil, held close to the scalp so that the field is focused in the brain cortex, passing through the skull.

Magnetic induction causes small local currents to flow within the brain tissue. When this stimulation is delivered at regular intervals, it is termed repetitive TMS, or rTMS. Recently, improvements in electronics have enabled machines capable of alternating these strong magnetic fields at physiologically interesting rates (up to 25 Hz), called high frequency rTMS.

In this study, researchers worked with ten stroke patients with the motor weakness over half of their body. The patients were trained to push a button with the fingers of their affected hand when presented with numbers flashed on a computer monitor. All the patients participated in the experiment twice, at a 1-week interval, and they were administered real or sham stimulations in a pseudorandomized order. Their performances on the tasks were measured by target scores and reaction time.

The results clearly showed that those who received the rTMS had better target scores and quicker reaction time than those who received the sham stimulation.

The study authors are encouraged about what the results may mean for rehabilitation of stroke patients. If future studies confirm the present results, rTMS may prove a valuable tool for restoring the functioning of stroke patients once immobilized by paralysis.

The AAEM is the largest organization worldwide (approximately 5000 members) dedicated to advancing neuromuscular, musculoskeletal, and electrodiagnostic medicine. The primary goal of the AAEM is to increase the quality of patient care, specifically for those patients with disorders of the central and peripheral nervous systems, neuromuscular junction, and skeletal muscles. This is accomplished through programs in education, research, and quality assurance. The AAEM believes that only physicians trained in electrodiagnostic procedures should perform needle electromyography and interpret nerve conduction studies to assure patients receive the proper diagnosis.