Next year you should be able to buy a small device that uses electricity to change your mood at the press of a button on your smartphone. The device, from a startup called Thync, currently consists of a set of electrodes connected to a phone. It has a short-lived energizing effect that feels a little like drinking a can of Red Bull.

Cofounder Jamie Tyler, a professor at Arizona State University, says the device can also be used to produce a calming effect more potent than drinking a couple of beers or taking Benadryl.

When I tried it, I felt relaxed but also clearheaded—more as if I’d meditated or received a good massage than had a couple of drinks. The effect took a few minutes to kick in, but then it lasted for about 45 minutes—although I’m told that varies from person to person.

Thync recently announced $13 million in venture capital from investors such as Khosla Ventures to bring the first products to market.

Marom Bikson, a professor of biomedical engineering at City College of New York, recently used a prototype of Thync’s device in a 100-person study (funded by the company) that focused on its calming effects. Bikson says the study showed “with a high degree of confidence” that the device has an effect, although the results varied. “For some people—not everyone—the effect is really profound,” he says. “Within minutes, they’re feeling significantly different in a way that is as powerful as anything else I could imagine short of a narcotic.”

The device uses a form of transcranial direct current stimulation (TDCS), something that’s been tested in various forms for years but has yet to be approved by the U.S. Food and Drug Administration to treat a specific disease.

In Thync’s device, a barely perceptible electrical current is applied to the skin on your head at different places for the Red Bull effect and for the relaxing effect.

Most TDCS research focuses on trying to use the electrical current to directly affect the outer part of the brain. Thync found that it was able to create strong effects by instead targeting specific nerves and muscles just beneath the skin.

Tyler’s ambitions extend beyond selling an electronic substitute for coffee. In separate work he is developing technology that uses ultrasound to affect the brain directly without surgery or drugs. “It’s a new frontier, with potential that hasn’t been tapped into yet,” he says.

The ultrasound work might lead to treatments for psychiatric disorders and offer new insights into how the brain works, says Amit Etkin, a professor of psychiatry and behavioral science at Stanford. He’s starting a partnership with Tyler that will investigate how the technology might help treat depression, post-traumatic stress disorder, and the tremors associated with Parkinson’s.

Etkin says ultrasound has two main advantages over other techniques: it can affect areas deep within the brain such as the amygdala, which is associated with emotions and motivation, and it is more precise, targeting areas that are millimeters rather than centimeters across.

But the ultrasound technology is at an early stage, and it will be hard to target specific parts of the brain reliably, he says: “It will require a lot more research before we really understand it.”