HAIFA, Israel and NEW YORK, N.Y., (April 12, 1999) -- Magnets have recently been hailed as the answer to a wide variety of ailments, but rarely have these claims been backed up by scientific evidence. Now a double-blind study at the Technion-Israel Institute of Technology shows magnetic stimulation of the brain eases severe depression, which affects some 10 million Americans.
The findings, which will appear in this month's Archives of General Psychiatry, provide convincing evidence that transcranial magnetic stimulation of the brain (TMS) is effective for treating severe depression and may become an alternative to electroconvulsive treatment (ECT), which causes painful convulsions and memory impairment.
The effectiveness of repetitive transcranial magnetic stimulation (rTMS), a refinement of TMS, was tested on 67 patients in a double-blind study -- in which neither the patients nor the researchers are told who is receiving the treatment and who is receiving the sham. At the end of two weeks, half the patients in the rTMS group showed a 50 percent improvement in their depression ratings. Only one-quarter of those in the sham-treated group showed the same improvement. Moreover, half the patients receiving the treatment had no need for further treatment with ECT, while all those receiving the sham treatment required it.
"Our findings are very exciting, since they provide clear evidence for the effectiveness of rTMS, at least over the short term," explained Dr. Ehud Klein of the Faculty of Medicine at the Technion and head of the Department of Psychiatry at Rambam Medical Center in Haifa. "The treatment holds the promise of eliminating the need for ECT therapy in many cases."
"It's a landmark work," said Dr. Mark George, professor of psychiatry at Medical University of South Carolina about the Technion research. His view was seconded by Dr. Robert Berman, assistant professor of psychiatry at Yale School of Medicine who noted that "Dr. Klein's group, which has been at the forefront of developing TMS, now corroborates earlier reports on the effectiveness of TMS with the first large-scale investigation."
The Technion findings are being further supported by a unique study now being conducted by Dr. Dorit Ben-Shachar of the research team and a co-author of the current study. Using brain tissue from laboratory animals, her research shows that rTMS causes biochemical changes, thus providing physical evidence that the treatment has a measurable biological effect. Her findings, first published in the Journal of Neural Transmission, Vol 104, have been accepted in Brain Research.
Both rTMS and ECT therapies affect the parts of the brain that play a role in causing severe depression, altering the metabolic activities in these areas. ECT stimulates the entire brain, is done under general anesthesia and causes painful convulsions and memory impairment that can last several months. rTMS directs a small electrical current induced by a strong magnetic field only on the prefrontal cortex behind the forehead. The treatment is repeated over short time intervals, is painless and has no side effects.
During treatment, the magnetic field is transmitted through a coil. The coil is held close to the scalp so the field is focused and the magnetic pulses can pass through the skull.
Unlike the electricity used in ECT, which gets diffused by the skull, magnetic pulses pass readily through bone to stimulate the neurons. Patients remain awake during treatment. Five patients in the Technion study (14%) reported slight discomfort due to facial muscle twitches, which was treated by reducing the stimulus intensity. Three patients (9%) reported a mild to moderate headache that lasted a few hours and responded favorably to paracetamol. None of the patients complained about impact on memory, concentration or other cognitive abilities.
The Technion team is starting a new clinical study that examines the efficacy of rTMS as a long-term treatment and as maintenance therapy, since depression tends to require ongoing treatment.
The Technion-Israel Institute of Technology is the country's premier scientific and technological center for applied research and education. It commands a worldwide reputation for its pioneering work in communications, electronics, computer science, biotechnology, water-resource management, materials engineering, aerospace and medicine, among others. The majority of Israel's engineers are Technion graduates, as are most of the founders and managers of its high-tech industries. The Technion's 13,000 students and 700 faculty study and work in its 19 faculties and 30 research centers and institutes in Haifa.
The American Technion Society (ATS) is the Technion's support organization in the United States. Based in New York City, it is the leading American organization supporting higher education in Israel. The ATS has raised a total of $713 million since its inception in 1940, more than half of that during the last seven years. A nationwide membership organization with more than 20,000 supporters and 17 offices around the country, the ATS is driven by the belief that the economic future of Israel is in high technology and the future of high technology in Israel is at the Technion. Technion societies are located in 24 countries around the world.
Journal
Archives of General Psychiatry