A new wave of wearable devices aims to help keep you calm and focused in times of stress. How? By running an electrical current through your brain.

Trying to control or alter the brain through electricity isn’t a new concept. In fact, the idea has been around for hundreds of years in the form of electroshock therapy. Fortunately, these new devices are a bit more sophisticated than hooking your brain up to a giant battery.

Change the Way You Think With Thync

Thync is a device that uses a pair of electrodes to run a carefully modulated electrical current through your head. It’s based on a concept called transcranial direct current stimulation, or tDCS. In tDCS, a low-level electric current is run through specific parts of your brain by means of an electrode placed on your skin. While tDCS has been proven to have a significant effect on motor control, its effect on cognitive functions has yet to be confirmed. While initial studies using tDCS as a means of treating depression have shown some promise, one scientific review found that tDCS had no consistent effect on people without mental health conditions.

However, neuroscientist and Thync co-founder Jamie Tyler says Thync is different. tDCS uses a constant low-level current, but Thync uses pulses of electricity instead. This allows the device to use a higher level of electrical current than would be possible with traditional tDCS. With a sustained current, three milliamps of electricity quickly becomes painful. In contrast, Thync is able to safely deliver up to ten milliamps in short pulses.

Tyler also has a theory on why the results from tDCS have been so inconsistent. Rather than affecting the brain directly, the electrical current may be stimulating the cranial nerves. Although they lie just beneath the skin, your cranial nerves are connected to the part of your brain responsible for controlling your fight-or-flight response.

In essence, this is what Thync was made to do. By stimulating your cranial nerves with different types of electrical current, Thync attempts to either suppress or enhance your fight-or-flight response. This should result in either a sense of calm or a feeling of intense focus.

Tyler also published a study supporting Thync’s effects. While the methodology is essentially sound, it’s worth noting that the study was published in an online journal that doesn’t require peer review.

So, does Thync actually work or not? Well, the definitive answer is: Maybe. Different people experience different sensations when wearing the device, from an intense feeling of calm to nothing at all. The brain is incredibly complex, and it’s hard to tell for sure whether these sensations are real or simply the placebo effect in action. What is certain is that even if Thync works, we don’t know for sure how it works.

Take Gaming Up a Notch With Foc.us

Thync isn’t the first attempt at a wearable device based on tDCS. Foc.us is a wearable device intended to improve focus for gamers. While Thync uses its own proprietary form of brain stimulation, foc.us instead uses a variety of existing methods. In addition to tDCS, foc.us includes options for transcranial alternating current stimulation (tACS) and transcranial random noise stimulation (tRNS).

Instead of a sustained direct current, tACS uses an alternating current to control neural oscillation. Like tDCS, its exact effects are hard to pin down, but it has been shown to increase alpha wave activity in the brain. Alpha waves are usually at their highest when you are relaxed but awake, such as during meditation. However, we don’t yet know for sure what role these waves play in brain function.

tRNS takes things one step further introducing completely random oscillations into the electrical current. This type of electrical stimulation has been shown to increase cortical excitability. Cortical excitability usually increases the longer you stay awake. If you’ve ever been jumpy or on-edge after pulling an all-nighter, this phenomenon may be partly responsible.

The technology foc.us is based on is sound, but it’s not completely clear whether these forms of brain stimulation have an affect on focus or mental acuity. However, the device’s wide array of options is intended to allow you to experiment and find something that works for you.

Control You Own Brain With Muse

Rather than attempting to alter the state of your brain, Muse is simply an observer, recording your brain waves using an electroencephalograph, or EEG. These devices have been used in hospitals for decades to measure brain activity, so the technology here is far more developed than tDCS. However, Muse doesn’t purport to help you focus, at least not in the same way as the other two devices. Instead, Muse helps you help yourself.

Using audio cues such as the sound of rain, Muse attempts to guide you to a meditative state. The alpha waves in your brain are at their strongest when you’re completely relaxed, and Muse can measure these waves. This sort of real-time feedback about your brain activity can help you learn to control it. That can lead you to a deeper and more relaxed state of meditation.

Electrical brain stimulation is already showing some promise for treating certain mental conditions, which could lead to more consumer applications. As the field advances, we may even see technology like this become commonplace. And although these devices may not work for everyone, one thing that is certain is their safety. Each of them has been thoroughly evaluated to ensure that the worst that can happen. . .is nothing.