Brain zapping. If you’ve heard of it, it was probably in the context of 1960s-style mental institutions and electroconvulsive therapy (ECT), neither of which look like very much fun. However, ECT is not the only type of zapping, or stimulating electrical currents in your brain, that doctors and scientists have been dabbling in during the past 50 years. As it turns out, ECT has a gentler, safer, and much less intense cousin called transcranial direct current stimulation, tDCS, which can be used for everything from minor mental maladies to improving memory and coordination, all in the comfort of your own home instead of one of those scary looking gurneys.
What tDCS Does
tDCS uses a fraction of the current in ECT, only 1-2 milliamps, which passes through brain tissue via electrodes placed on the scalp. The stimulation is too weak to directly cause neuronal firing, but is thought to interact with the neuronal membrane and background neural activity. It can induce lasting changes in neuronal excitability, the intensity with which your neurons react to stimuli. A tDCS device is like a small, handheld battery that fuels spongey electrodes, which clip to your head. Attaching these to different parts of the head can affect many different mental processes, from language learning to solving math problems, so if you’re looking to become a math guru, this might help!
One example of the importance of stimulating different parts of the brain: putting an anode over the motor cortex and cathode over the contralateral supra-orbital region produces a lasting increase in motor cortical excitability, but when the electrodes are reversed, a decrease in motor cortical excitability is seen; it’s important to know what you’re zapping! The efficacy and duration of the tDCS-induced neuronal changes in humans depend on length of the stimulation, size of the electrodes, and strength of the current.
tDCS was originally developed in the 20th century by the military, which studied whether brain stimulation could cut down pilot training time. They’ve also measured if tDCS improves visual recognition, and have found that tDCS made airmen twice as accurately identify tanks and missile launchers in radar scans, as well as their improving abilities to detect hidden threats – which is important, whether you’re in the military or walking to your car at night in a sketchy part of town.
On a chemical level, tDCS has big effects on your brain. Using this sort of stimulation increases levels of the neurotransmitters glutamate and glutamine. Glutamate is the main chemical messenger in the brain, so having more of it gives your brain a greater capacity to send messages and process information. tDCS also raises levels of NAA, a strong indicator that your neurons are healthy. Together, all of these chemicals stimulated by tDCS support learning and brain adaptations; the more, the merrier (to an extent). On the flip side, researchers have documented almost immediate decreases in these neurotransmitter surges at the end of stimulation sessions, so getting your learning in during the tDCS session is essential. That said, the learning you’ve done does not fade, and studies have shown that there’s a cumulative effect on overall learning – consistent tDCS use may make neurological changes in your brain that make your brain function and learning more efficient, even without stimulation.
tCDS is Used for a Variety of Reasons
Using tDCS at Home is Simple
If you’re itching to try out tDCS at home, there are a few options for purchasing your own kit. Foc.us is a company that makes adequate tDCS kits; they’re marketed towards athletes, but are great for everyone. Omni Stimulator and the Brain Stimulator also sell quality products.
Before you start hooking up the electrodes:
Doing a session for longer than 20-25 minutes could potentially be harmful, as can doing stimulation sessions too often. Most practiced users will use tDCS 3-4 days per week, but it’s important to work up to that level instead of jumping on in!
Be Smart About Getting Smarter
Something to be mindful of, in spite of the positive benefits of tDCS, is the notion that enhancing one cognitive ability can happen at the expense of another. Think about savants, who have incredible mental gifts in certain areas, yet struggle tremendously in others. That’s not to say that using tDCS will damage your brain or impair your learning if used properly, but there have been some reports of increased introversion and other slight but notable mood changes during and briefly after tDCS sessions.
As with anything that effects that brain, there are some risks. However, it has been proven many times that tDCS can be safely used, both by doctors and patients. Just make sure that before you start improving your memory, you understand where, how long, and at what intensity you need to be stimulating – most products come with instructional manuals, and DIY TDCS is a great resource for more information for the at-home user.
Now that you know how, get out there and get stimulating!
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