In research published on November 18 by the journal Frontiers in Human Neuroscience, scientists demonstrated that the device, which uses vibrations to send signals to the brain, can disrupt the rhythms that cause resting tremors. In Parkinson’s, these tremors occur when muscles are relaxed, according to the National Institute of Neurological Disorders and Stroke. If you have the condition, your hands, arms, or legs may shake even when they are at rest, the institute says. “Tremor can often get in the way of activities of daily living by affecting mobility and balance, so a noninvasive, nonmedical way of addressing these tremors is very exciting,” says David F. Putrino, PhD, the director of rehabilitation innovation for the Mount Sinai Health System in New York City and a coauthor of the study. “When we applied this stimulation to people with Parkinson’s disease, it wasn’t annoying or painful, and it seemed to reduce their tremors.” The results will need to be confirmed in large-scale clinical trials “with people with Parkinson’s disease wearing the device day in and day out” for extended periods before it can be made available for use, according to Dr. Putrino.
Existing Treatments Target the Brain
The device in this study isn’t the first approach that has involved the delivery of vibrations or pulses of energy to the nervous system, the American Parkinson Disease Association (APDA) notes. Two surgical procedures, deep brain stimulation (DBS) and high-intensity focused ultrasound (FUS), have been used for years. In FUS, surgeons apply beams of ultrasound waves to a designated target in the brain, creating enough energy to form a small lesion, which can disrupt abnormal circuitry in people with Parkinson’s disease. Meanwhile, in DBS, a surgeon inserts thin electrodes into the regions of the brain that control movement, the ADPA says. These electrodes, which are connected by a wire to a pulse generator that is implanted under the skin in the chest, deliver tiny electrical pulses that allow the brain to maintain normal movement activity. Researchers have also explored whether having people with Parkinson’s disease exercise on a vibrating platform improves tremor and other symptoms. Results have been mixed so far.
How the New, Noninvasive Device Works
Although the wearable device developed by Putrino and his colleagues works in essentially the same way as DBS, it doesn’t involve surgery, and it targets the peripheral nervous system, or the body’s nerves outside the brain, instead of the brain itself. It also can be controlled by users with a mobile phone app. The device — which is “the size and weight of a wristwatch,” Putrino says — can deliver two types of pulses. The first is “constant, very low threshold, very gentle” and it “feels like a gentle touch or tickle on the inside of the wrist or ankle,” he notes. “Users barely noticed it,” he adds. The second is more intense, but not continuous, according to Putrino. “It’s stronger, more pulsing, more obvious, and it feels like a heartbeat on the inside of the ankle or wrist,” he explains. In this most recent study, 44 people who had Parkinson’s disease and experienced resting tremors wore the device on their ankles or wrists for a short time — several 10-minute sessions. Wearers saw a reduction in tremors while receiving both types of vibrating pulses, with no reported side effects, the researchers say. Although the technology doesn’t seem to have lasting effects — meaning the reduction in tremors stops once you remove the device — it does provide relief while in use, according to Putrino. In addition, it’s powered by a battery that can last all day if it’s charged overnight, he says.
Larger Studies Needed to Determine Optimal Dose of Vibrations
Putrino and his group are in the process of securing funding to conduct larger clinical studies of the device. Part of what these studies will need to determine is “the minimum dose of vibrations needed to achieve the desired effect,” and whether users will need to wear more than one device at the same time for the best results, he says. “In people with Parkinson’s disease, the areas of the brain associated with producing body movement start signaling too much,” Putrino notes. “However, when we apply this vibration, we’re sending a pulse of energy up into the brain to disrupt this signaling. It’s not a dangerous intervention in any way, shape, or form, and it seems to work well.”
