Therapy borne on electrical currents

BRAIN WAVES Thync is the latest in transcranial direct current stimulation, or tDCS. Kira Peikoff finds out more about this device that can alter a us

I  draw an uneasy breath as I step into a bright purple office on the fourteenth floor of Boston’s Prudential Building. I am shown to a small conference table, where I take a seat and await the experiment. A palm-size, triangular module is affixed above my right eye. It connects to a single-use strip of electrodes stuck onto my forehead and running down the back of my neck.

This is Thync, the latest in transcranial direct current stimulation, or tDCS. The manufacturer says the device, to come out later this year, can alter the user’s mood in minutes via electric current. With a connected smartphone app, the mood-impaired subject chooses one of two settings: “calm vibes” or “energy vibes.” I tap “calm vibes” and wait. Somehow, I am having a hard time picturing myself unwinding at home this way while my husband sips a glass of merlot.

Thync is the latest in a wave of wearable gadgets offering so-called non-invasive brain stimulation. Until recently, it was mostly hobbyists – nine-volt batteries stuck to their heads – who experimented with tDCS as a means of improving concentration, verbal and computation abilities, and creativity. But in the last few years, several companies have introduced slick consumer devices, among them Foc.us, whose headset and controller cost $298, and The Brain Stimulator, whose advanced starter kit costs $150.

In January, the journal Brain Stimulation published the largest meta-analysis of tDCS to date. After examining every finding replicated by at least two research groups, leading to 59 analyses, the authors reported that one session of tDCS failed to show any significant benefit for users.

Now the developers behind Thync are aiming to redefine the product category by introducing a new, proprietary form of tDCS that they say more reliably produces the intended effect.

Originally, tDCS targeted a specific brain region by sending an electrical current first through the skin, skull, blood vessels, cerebral fluid and meninges. Some researchers say that approach makes it difficult to determine where the current actually enters and exits the brain.

Thync’s strategy is to bypass the brain and instead use pulsed currents to stimulate peripheral nerves closer to the surface of the skin, with the goal of modulating the user’s stress response. “We spent a year and a half optimising the wave forms to the point that we felt really confident in the science,” said Jamie Tyler, the company’s chief science officer. His team has tested about 3,300 people in single-blind and double-blind, placebo-controlled studies.

Wave forms refer to a series of electric pulses that change frequency and amplitude over time. Like a sound equaliser, the theory goes, the parameters can be “tuned” to produce an intended biological effect. Soon into my 20-minute demonstration, I feel a sharp, slightly painful tingling above my eye, like vibrating pinpricks. I brace myself, awaiting relaxation.

According to Jamie, the “calm vibe” at its peak produces a relaxation greater than that provided by three Benadryls, according to a common statistical measure for effect size.

The “energy vibe” is said to be stronger than that produced by a 20-ounce can of Red Bull. Each mood lasts for about 45 minutes without a subsequent crash, Thync says. But some experts are skeptical, insisting that the company show evidence of peer-reviewed, independently replicated results. “ I do think it’s a bit early in the game to be putting this rather untested and unknown technology out there as a kind of big societal experiment,” said Rex Jung, a neuropsychologist at the University of New Mexico-Albuquerque, who has conducted government-funded research of tDCS.

Thync posted one study of 82 subjects on bioRxiv, an unmonitored open source website for unpublished research. The study measured only the device’s calming effect, and company researchers concluded that it induced “significantly greater subjective relaxation” compared with placebo stimulation.

The participants first underwent no stimulation, then real stimulation, leading some experts to question the study’s design. “It’s difficult to determine if the change in relaxation was due to stimulation or due to participants sitting comfortably for 40 minutes,” said Jared Horvath, a fourth-year PhD student at the University of Melbourne and lead author of the recently published meta-analysis on tDCS.

While Jamie said Thync’s test subjects have not experienced significant side effects, some experts sounded a note of caution for potential consumers. “Almost all interventions of this sort have some sort of side effects,” Jung said. “Is the cure worse than the disease when you’re talking about changing the circuitry in the peripheral nervous system?” After 15 minutes, I feel a mild tightness in my head though the tingling sensation has abated. I’m not floored by sudden calm, but my breathing has deepened.

If Thync does work, some mental health professionals worry it could distract users from developing their own coping skills. “The practice of learning to change yourself can be very powerful and also give people the skills of self-regulation that can last longer than a device,” said Carl Erik Fisher, an assistant professor of neuroethics and psychiatry at Columbia University But Thync’s developers say that it can help users “conquer life.” In a recent real-world test, they gave it to 12 people before first dates. Eleven reported that the calm vibes had improved their experiences. (The twelfth subject thought he became too mellow, but his date called him a good listener.) After 20 minutes, I remove the electrodes, yawn and saunter out. Whether the effect is real or a placebo, I can’t say, but I do know one thing: It’s time for a nap.
NYT