Scientists warn of side effects of poor electrical brain stimulation

She uses a non-invasive method micropolarization

When it comes to the neurostimulator, most habitually reaching for a cup of coffee (caffeine), green tea (caffeine and theanine) plitochki or dark chocolate (flavanols). More advanced users know about modern nootropics, including synthetic, which increase efficiency, concentration, improve working memory, speed up the processing of visual information, etc. Even more sophisticated are aware of the great effects that give the exercise .

However, science does not stand still. Recent advances in neurology allow you to act on the brain without the help of chemicals, but directly. For several years, neurohackers and transhumanists have been experimenting with micropolarization (tDCS), a treatment method that can improve the functional state of various areas of the brain using a small direct current (up to 1 mA or a little more).

The method of brain stimulation is very simple, non-invasive and available for use even at home.

Equipment for micropolarization too simple: the battery and two electrodes with sponges, which are soaked in salt water and applied to the place of the head, where there is an appropriate part of the brain to stimulate. You can squeeze the usual headband that sports brands produce.


Commercial machine DC Stimulator Plus for electrical brain stimulation

on Reddit and other forums on the Internet users share their experiences and publish instructions where to put the electrodes for the appearance of the desired therapeutic effect (see. Podreddit / r / tDCS / ).

Enthusiasts of the hacker movement claim that electrical stimulation of the brain will give a better effect than nootropics. According to the words of advanced experimental, with proper application micropolarization effect can be compared with taking modafinil, which is used for other purposes to enhance cognitive function and eliminate sleepiness.

Scientists are not surein the effectiveness of micropolarization. The fact is that a current of 1-2 milliamps is not enough to activate neurons. Such weak stimulation can only bring them into a state of “readiness”, that is, increase the likelihood of their activation and the establishment of new connections. It is rather difficult to study this effect, although various studies have been conducted on the use of micropolarization for the treatment of depression , anxiety disorders , and the effects of stroke . Experiments in Australia show improved cognitive abilitiespatients in solving mathematical problems during electrical brain stimulation. At the same time, this method is not an officially approved treatment for any disease or disorder. Officially, it is still considered an experimental treatment.


Solving math problems during electrical brain stimulation. Photo: Thomas Weickert, Neuroscience Research Australia

In addition, the scientists point out that contrary to popular opinion in popular culture, the functional areas of the brain do not have a clear position. Each person has an individual brain map, with its own characteristics.

However, this does not stop experimenters who are “treated” at home and try to stimulate various areas of the brain, checking the effect on themselves: in which cases drowsiness disappears, in which memory is supposedly improving.


Lisa Arnold (Lisa Arnold) anode placed behind the left ear, presumably, in the motor area of the brain, and the cathode on the right hand, in order to cause a sense of euphoria

In principle, to date, doctors have not objected to such experiments, because there was no clear evidence of the harmful effects of a weak current. Although a brain scan shows that there really is some kind of effect, scientists cannot reliably predict how it will manifest itself, that is, how a specific person will react to a specific effect in a specific area of ​​the brain. This is a purely individual process, and while laboratory tests give unpredictable results.

Previously, doctors had nothing against experiments, but now objections have nevertheless appeared. A group of scientists made an open letter , published July 7, 2016 in the scientific journal Annals of Neurology. Experts speak out against electrical brain stimulation at home, warning of possible side effects. They believe that short-term improvements in some cognitive abilities may occur due to other abilities. Ultimately, it can harm the brain in the long run, they say.

Scientists mention that some negative side effects have already manifested: for example, possible slight skin burns in case of its hypersensitivity. Other side effects are not entirely clear, and this mystery is even more alarming to specialists. For example, there is evidence that the effect of brain stimulation manifests itself in different ways, depending on what a person is specifically doing. The effect is different if a person reads a book, meditates, focuses his eyes at one point, does math problems, sleeps or plays computer games.

Apparently, even the time of day affects the effect of brain stimulation, for unknown reasons.

“We observed different types of responses [to micropolarization of the brain],” saysVurzman Rachel (Rachel Wurzman) from the laboratory of cognitive and neurological stimulation of the University of Pennsylvania, co-author of the open letter. Maybe every third person will have a inhibitory effect on a certain type of stimulation. At the same time, in another third, the effect can be exactly the opposite, and in the rest - no effect at all. All this extremely complicates the scientific research of micropolarization. Scientists believe that under such conditions caution should be exercised.

“The networks of neurons in the brain interact with each other, so changes in the activity of one network can affect others,” the authors of an open letter write. Stimulating one part of the brain can impair the performance of other areas of the brain. “For example, micropolarization can speed up the learning process, but this will happen due to the quality of processing of the acquired material, and vice versa, depending on the place of stimulation.”

Scientists admit that they have never done long-term studies of the effect of electrical stimulation on a daily basis for several months. In such experiments, they are inferior to the enthusiasts who set and continue to put such long-term experiments on themselves. But based on the available data, scientists suggest that the effects of micropolarization can persist for at least six months.



Over the course of six months, positive and / or negative effects will persist. In general, home-based neurohackers should understand the potential risks before connecting electrodes to gray matter.