Research on the nonsurgical use of nerve stimulation to treat problems like chronic pain, depression, hypertension and stroke is advancing in the Mass General laboratory of Vitaly Napadow, PhD.

Imagine a device worn like a wireless earbud that could detect the body’s changing rhythms and normalize them by electrically stimulating specific nerves — lowering blood pressure, easing pain or depression without drugs or perhaps assisting in stroke recovery. Massachusetts General Hospital researcher Vitaly Napadow, PhD, is developing a device that may someday do that.

“Recently, we’ve gotten better at understanding what parts of the brain we need to target and developing guided therapies to target them.”

Dr. Napadow, director of the Center for Integrative Pain Neuroimaging at the hospital’s Athinoula A. Martinos Center for Biomedical Imaging, is working with a company called Cala Health, Inc., to create and manufacture wearable devices that will then be tested with patients.

The device uses “neuromodulation,” that is, stimulating nerves with electrical impulses. Nerve stimulation as a way to change abnormal nerve activity is not new, especially for pain relief.

“But it’s only recently,” Dr. Napadow says, “that we’ve gotten better at understanding what parts of the brain we need to target and then developing guided therapies to target them.”

Stimulating Nerves without Surgery

For the past 10 years, he has been researching nonsurgical ways to stimulate and change the activity of the vagus nerve, which is part of a nerve circuit that links the brain with the heart, lungs, gut and other bodily organs. The vagus nerve affects functions such as digestion, blood pressure and breathing rate.

Vitaly Napadow, PhD
Vitaly Napadow, PhD

There’s an FDA-approved surgical way to stimulate the vagus nerve in the brain to lessen certain seizures from epilepsy. But scientists now know that there are vagus nerve receptors on the skin at a specific part of the ear that can also be stimulated. A device targeting them would be much less intrusive than one that is surgically implanted.

“Our novel approach to improve the targeting of these surface receptors is to time the nerve stimulation to the respiratory cycle,” Dr. Napadow says, referring to the cycle of breathing air into and out of the lungs. “This whole brain/vagus loop may be sensitive to the body’s breathing cycles, much like our heart rate speeds up whenever we breathe in and slows down whenever we breathe out.”

His plan is to target these surface receptors with an earbud-sized device worn in the ear. The device will be programmed to monitor somebody who is breathing. Then, based on which phase of the respiratory cycle they’re in, the device is programmed to decide when to provide nerve stimulation.

Potential for a Variety of Problems

Dr. Napadow’s research team has investigated this nerve stimulation approach for treating a variety of conditions, including chronic pain, migraine, depression, hypertension and stroke. “We want to create devices that are safe, effective and help a wide range of different patients,” he says.

There is much potential for a wearable device that will non-invasively help people stay pain-free or healthy.

Currently, Dr. Napadow is working with Cala Health to develop an actual device patients can wear home in a clinical trial.

He sees this work as a natural extension of his research into non-drug pain treatments, including efforts to understand the effects of acupuncture, cognitive behavioral training and mindfulness meditation on brain activity.

He recently received a large grant from the National Institutes of Health to study the potential effect on pain of mindfulness training in combination with his respiratory-targeted vagus nerve stimulation. Mindfulness training, focused in part on breathing, may enhance the efficacy and brain targeting of his respiration-gated approach to stimulating the vagus nerve, he suggests. And vice versa, his respiratory-gated approach may enhance the effect of mindfulness training.

There is much potential for a wearable device that will non-invasively help people stay pain-free or healthy, he points out. “But much more research remains to be done to see which patients will benefit, and from which specific approach.”

For more information on how to support the work of Dr. Napadow and other researchers at the Martinos Center for Biomedical Imaging, please contact us.