Direct current brain stimulation

A couple of weeks ago I finally found the courage to pump my brain with direct current as I read a very complex mathematical paper. I bought a very simple device called “The Brain Stimulator” and used “improving insightfulness” setting. The electrodes were moist and warm and quite pleasant. The device was extremely easy to operate and it appeared to be working. I understood the article better than when I looked at it an hour before. My only regret was the length of the session. 30 min is not enough for most of the activities where I need to be focused. Happy with the results, I had several successful sessions since…

Brain stimulation, especially direct current brain stimulation is slowly getting scientific recognition as one of the safer forms to boost mental abilities. I quote from Scientific American:

This form of attempted brain hacking—known as transcranial direct current stimulation (tDCS)—is not as far-fetched as it might sound. The brain runs on electricity. Brain cells build up charges that impel chemical signals across synapses, the tiny gaps between neurons. When we learn something, the synapses involved become conditioned to fire more readily, and tDCS supposedly enhances that process. The tiny electrical currents tDCS uses—generally one to two milliamps—cannot actually trigger the chemical impulse that crosses a synapse, but some researchers believe tDCS strengthens synaptic connections to make learning more efficient. Small lab studies suggest it can improve vigilance and reaction times. “You get more bang for your buck” by combining tDCS with conventional training, contends Marom Bikson, a professor of biomedical engineering at the City College of New York.

You can find more here, here, here, here, here, here, here and here.

So, why did I start using this device? I have been reading a lot of researchers about the subjects and eventually, I felt I needed to try it on. There are very few side-effects to tDCS. Some itching where tDCS is applied is quite normal. Other effects are more related to enhanced brain activity: sensitivity to light and noise and general tiredness. It is not recommended by scientists to have sessions longer than 30 min, and after the 30 min, I personally need a short nap or a walk outdoors. This is not bad for a device that can significantly increase the ability to solve mathematical problems, remember better what we read, decrease pain and depression, and even improve driving or gaming skills. If we were using chemical methods, the side-effects would be much more significant.

There were many attempts to modify the brain activity using electricity and magnetism. In 1780, Luigi Galvani discovered that the muscles of dead frogs’ legs twitched when struck by an electrical spark. Soon after, electrical brain stimulation was used by researchers such as Luigi Rolando and Pierre Flourens. The initial experiments have been very violent, with awesome results and equally awesome side-effects. With time, the experiments became safer, milder very localized to specific areas of the brain. For example, the apparatus of magnetic brain stimulation can even activate “remotely” various areas of the brain in an orchestrated succession. The most effective and accurate devices use many electrodes or inductive sources, have complex brain mapping and timing mechanisms and are obviously expansive. The cheap and safe devices typically use direct current stimulation with just two electrodes. They have more subtle effects, and only around the year 2000 very rigorous cognitive research was able to prove the effectiveness of this devices.

The simple tDCS devices cost around 100USD. They include a small DC converter with two wires that are effectively the electrodes. The electrodes are connected to large wet sponges which are kept on the user’s head with the help of something looking like a headband straight from the 1980s. Some saltwater is applied to the sponges, so the sponges need to be washed after each usage. That’s it. The placement of the electrodes is important. Simply reversing the polarity of the electrodes, we can probably reverse the effect of the current application. There are several online diagrams of the electrode placements that have been proven in large-scale experiments. Thousands of scientific papers with various large-scale experiments have been published during the last couple of years, and each month there is a new strange and wonderful effect contributed to some particular placement of the electrodes.

For example, tDCS stimulation of the amygdala area of the brain has been linked to improving the memory. The amygdala is not a fear center of the brain. Applying the stimulation to amygdala did not cause panic attacks, paranoia or aggressive behavior. Instead, almost 80% of the small group of participants instantly improved their ability in image memorization and recognition. By timing the learning activities and brain stimulation, the scientists were able to mark and prioritize the information that needed to be remembered. The neuroscientists speculate that the amygdala has an ability to modulate memory-consolidation processes in other brain regions, such as the hippocampus and perirhinal cortex.

Learning a language using tDCS seems like a good idea. Several people tried it and report excellent results. Here is an example of such study. Results showed that stimulation to the area called “left angular gyrus” resulted in a faster comprehension of meaningful relative to non-meaningful word pairs. Applying the similar current to the “right angular gyrus” did not produce such an effect, which shows that the stimulation is specific.

A totally different direction of tDCS study has to do with the brain’s ability to differentiate visual and auditory stimuli and quickly react to them. Darpa is currently sponsoring several kinds of research, which show that during brain stimulation gaming abilities improve. This includes spotting suspicious behavior, driving, shooting, and so on. Here, by stimulating prefrontal cortex in apes, the researchers improved the learning experience by 40%. It could be easy to dismiss experiments on apes, but there were similar experiments on humans. As elderly people have difficulties remembering things, stimulation of the prefrontal cortex or related regions helps the elderly remember and function properly.

The brain stimulation can modify the libido. Is it OK to use it to modify someone’s sexual preferences? While chemical treatment is very effective for boosting and neutralizing sexual drive in men, tDCS might target women’s libido. There are some major studies on the way, and eventually, some ladies may choose to wear a small headband to get into the mood.

Half an hour of learning is not much. Being a practical person, I will try to outline the situations where I see the tDCS’s potential:

• Complex texts. Occasionally, not very often, we need to handle texts that are very complex. We may need any help we can get simply not to get stuck reading the text.
• Specific memorization. Some words, numbers and historical details simply need to be memorized in a way that is very hard to forget. We can prioritize what we must remember, and supercharge the brain while memorizing the top priority information.
• Expensive training. Some training, like webinars, may be expensive, time-limited of otherwise scarce. We may want to get the best results during the training session.
• Getting out of the comfort zone. Any result we can achieve using tDCS, we can probably achieve without it after some training. By experimenting with our potential, we get enough courage and confidence to try the hard things without the electrodes.

I wish I could publish an optimal placing of the electrodes for important scenarios. This is not the case. There are several positions of electrodes, which boost specific combinations of skills, all of them helpful in some way to our goals. For example, for the next 30 minutes: do you choose to be more insightful, better in generating associations, or more accurate in understanding the subtleties within the text?