Worn for about 20 minutes a day, the headbandlike device would provide electric stimulation—which temporarily suppresses symptoms like general slowness, limb weakness, muscle tremors and speech difficulties—to a patient’s brain in the comfort of the patient’s home.

It would be a big change from how electric stimulation is currently applied: A patient must undergo brain surgery to implant metal signal-receiving rods in affected areas of the brain. Then, when electric stimulation is applied to the patient’s head through an implanted pacemakerlike device, the rods pick up the current, and symptoms subside. Electric stimulation can be used in addition to medication.

When a group of Johns Hopkins biomedical engineering graduate students learned about a noninvasive brain stimulation method at the Laboratory for Computational Motor Control, they wondered if the treatment could be provided in patients’ homes. They turned to Yousef Salimpour, a neuroengineer at the Johns Hopkins University School of Medicine, and his team, who have been developing the approach.

In Salimpour’s method, a doctor places electrodes on a patient’s head to deliver transcranial direct current stimulation to parts of the brain affected by Parkinson’s disease. But the electrodes must be placed just so, the current must be only so strong and delivery can last for only a certain length of time.

The students incorporated the electrodes into their easy-to-wear, 3-D printed prototype, which can be programmed by a doctor to deliver just the right amount of current for the right amount of time at the patient’s touch of a button.

Preliminary results are promising, and the team has taken out provisional patents on the device. Approval from the Food and Drug Administration, which could take several years, is needed to begin clinical trials.