Can You Use Electricity to Supercharge Your Brain? | tDCS

Can You Use Electricity to Supercharge Your Brain? | tDCS

People around the world are strapping batteries
to their heads to supercharge their brains. Seriously. This is a thing. It’s called transcranial direct-current
stimulation, or tDCS, and it involves using electric currents to stimulate your brain. The companies that want to sell you tDCS devices
claim that it has all kinds of benefits: They might say that it’ll boost your memory
and focus. Some even claim that it can do everything
from treat depression to help you sleep better. If that sounds too good to be true — it
is. Ah, the truth is a lot more complicated. Studies have found that tDCS might help with
some things. But there’s also plenty of controversy about
it among scientists, and the jury’s still out on how exactly tDCS affects the brain. Even though it involves electric currents,
tDCS is a lot less intense than the kind of supercharged electric shocks used in electroconvulsive
therapy That’s the more famous electricity-related
therapy that’s sometimes used to treat things like really severe depression. A tDCS headset contains two electrodes, called
the anode and cathode. The idea is that the anode will boost the
area of the brain beneath it, whereas the cathode will inhibit the area beneath it. The choice of those areas, of course, depends
on the particular functions you’re looking to play with. Once everything’s in place, a small electrical
current of around 0.5 to 2.0 milliamps is sent through the electrodes, right into your
head. Since the current is so small, it’s not
painful — as long as you set it up properly. The most people tend to feel from this kind
of current is a mild tingling sensation on their scalp. A tDCS session typically lasts around 20 to
30 minutes, and people usually do a number of sessions over the course of a few weeks. The thing is, most people doing this at home
might be making their scalps tingle for nothing, because we still aren’t sure if tDCS actually
does a lot of the things companies selling these devices are claiming. Entering the world of tDCS experimentation
has a pretty low bar, since headsets are fairly inexpensive. Unfortunately, that’s made the literature
a little … messy. One problem is that we still aren’t totally
clear on what tDCS does to the brain on a physiological level. We do know that current can affect the way
neurons fire, and researchers think that the mild current from the electrodes changes the
membrane potentials of neurons, allowing them to fire more easily. The idea is that, with enough stimulation
and repeated exposure, the neurons that are getting the stimulation will start firing
more. Over time, that might nudge damaged or underperforming
brain areas toward functioning in a healthier way all by themselves. But this is all still the subject of some
debate. One study, published in 2016, used a cadaver
to measure how much current from tDCS managed to travel through the skull to the brain. Electrodes placed on the inside of the skull
showed that around 90% of the electricity applied through tDCS didn’t get through
at all. That study raised a few eyebrows, but according
to a lot of tDCS experts, the findings actually make sense, since live tissue is better at
conducting electricity. Plus, there’s a lot of evidence that tDCS
affects brain function, so there must be some amount of current – however small – making
it through. Which brings us to the other main problem
when it comes to tDCS: we still don’t know exactly what effects it has. A lot of tDCS studies are small, pilot studies
that need to be replicated before we can draw any conclusions from their results. And some aren’t so tight in the methodology
department. In meta-analyses that look at results across
multiple tDCS studies, researchers have pointed out that the methods used in different studies
are so inconsistent that it can be hard to compare them. There is some well-designed tDCS research
out there, though, and based on those studies, researchers have found that it might be an
effective treatment for mood disorders, psychosis, and dementia. It might even help people recover from strokes. A 2016 meta-analysis of 17 studies found that
stroke patients who did tDCS treatments regained more motor function than patients in the control
groups, who did fake tDCS treatments. Scientists are also looking into tDCS as an
alternative treatment for depression. A meta-analysis of data from six randomised
control trials, with 289 patients in all, showed that tDCS relieved symptoms of depression,
even in people who’d felt no benefits from medication. But that’s the thing — researchers are
still looking into all this. tDCS seems like it could be really promising,
but there’s a lot we still don’t know. Sure, some studies have found that tDCS helps
stroke patients recover their motor function, but that doesn’t necessarily mean that it’ll
give healthy people better motor function in general. Plus, these studies are done in a clinical
setting, which is totally different from buying a device and giving yourself a tDCS treatment
at home. If you put the electrodes just a couple of
centimeters off from the right spot, or the current is slightly lower or higher than it
should be, you might end up stimulating your brain in a way that’s completely different
from what you wanted. So, there is some solid evidence that seems
to point to tDCS being a useful therapeutic tool in the future. Just … maybe don’t run electric currents
through your brain on your own until we know a little more.  
Or do, I’m not your dad. But I will tell you that for the cost of your
average tDCS device you could become a significant SciShow Patreon patron, and we would really
appreciate that so that we could make more great stuff for the whole world to have for
free. And you can do that at,
and if you just wanna help us up by subscribing, you can go to for
more brain stuff, every twice a week.

100 thoughts on “Can You Use Electricity to Supercharge Your Brain? | tDCS

  1. How does this stimulate the brain when the path of least resistance is across the scalp where there is soft tissue?

  2. "We still don't know exactly what effects it has" is the mantra of psychology – has been since day one. The only field of 'science' that allows this :/

  3. Well I'm intrigued to see what becomes of this, but I'm definitely not going to be messing around with this. I'd rather not mess up my brain further.

  4. Unsubscribing due to your "Vidcon bias" Hank Green!; thought you might be objective, but you are not. You caved. Reject reality and insert your own?

  5. Where's the TED talk where the lady scientist tells Chris that there have been amazing results and that the U.S. military is calling but she isn't answering?

  6. The whole time I was watching this, I was so distracted, wondering who my real father is. Is Hank Green my father?!
    Finally, at 4:57, I learn that my seemingly endless search must continue. ?

  7. …This is like the old weight loss belt. Instead of becoming a jock without working out, it's becoming a nerd without studying.

  8. But you might be electroplating your brain lobes with the random metal ions in the brain blood flow; and then when you remove the applied potential the electroplating acts as a discharging battery restoring the previous ion distribution—when you least expect it… (Caution, Do not test this theory without qualified neuroscientist supervision)….

  9. "Ooh!! I'm gonna run electricity through my brain because I saw an advertisement on the Internet that told me it'd be good for me!!!!"

    Who the hell thinks like that? I don't understand people who buy into these fads.

    If research proves that it genuinely helps people who have actual problems with their brains, then that's great! But let's wait for the science to catch up with the marketing hype, shall we?

  10. It sounds sort of similar to the idea behind rTMS treatment except rTMS is done by professionals and has evidence behind it.

  11. I really appreciate that SciShow never gives plain yes or no answers but takes its time to explain that science is a bit more complicated than that. Not only does it make the content more factual but it also shows that audiences aren't as stupid as a lot of science journalism makes them out to be.

  12. Huh?? 10%? Like, 200uA?! But isn't bone supposed to be a pretty good isolator???
    (and bone is always a dead tissue, except bone marrow which a skull does not have)
    Anyway randomly electrolyzing the brain does not sound like a sane idea at all.
    Hopefully the studies are fake and all of the electricity goes through the skin. Hopefully.

  13. Why isn't this being studied more rigorously? As inexpensive as the actual treatment is, any potential benefit, however small, should be worth the research, shouldn't it?

  14. a company selling a product and that product doesn't do what the company says it is supposed to do. that's news to me : l

  15. You can build one from the tutorial on my channel. The devices sold commercially don't really work. To repeat research studies current density and electrode size are important.

  16. A few years back, saw a counselor who let me try something like a tDCS for a few sessions, only his used a very low voltage, high frequency, alternating current, and the contacts were clipped on to the earlobes. It SEEMED like I got substantially better sleep quality the night of the treatment – but that may have well been wishful thinking.

  17. The "OMNI stimulator" is the least expensive. Less than a hundred. I've been using one DAILY for 8 months now to treat depression. I'm off meds and I feel NORMAL. It works for me.

  18. The cadaver used in the study showed distinct homicidal tendencies, but a marked improvement in language utilisation. He was later trapped in a mill and burned by an angry crowd of villagers.

  19. welcome to psychology. welcome to science. Individual variability is the norm, therefore effects will vary even if the treatment is exactly the same. We can pull up plants checking and arguing there is no growth, but that only does one thing.. stops growth. This incessant cry for "more research, more research" are like a chorus of green tree frogs… sometimes the evidence is there but the group think is so strong that the "royal WE" argues, "we don't know enough at this point." Who are we????

  20. Question: is this the same as TMS treatment (transcranial magnetic stimulation)? I’m getting that done right now and it seems more intense than this. Would you ever maybe do a video on TMS? I’d love to hear your perspective on it!

  21. After Faraday discovered electricity, people in the 19th century fell for the same sort of hype & wasted money on machines that also zapped you!

  22. Or people could try exercise to increase blood flow to their silly little brains.  But noooooo.
    That makes me sound bitter & grumpy.  Quite right.

  23. something we all need to know, as a fact, is that any external electrical exposure will damage the nerves (and of course, slightly chances to gain cancer is another option as always)

  24. I tried this with a tens unit. I put one electrode near each of my temples and it made me focus extremely hard for a couple hours but I feel like I was dumber the next couple days

  25. I was medically treated with this at a headache clinic, after a severe Traumatic Brain Injury – All i ever got out of it was: sick to my stomach.

  26. 4:57 – "Hey folks, our conclusion is simply this: Touch a nine volt battery to your tongue instead, and give the rest of your money to us."

    * I love SciShow, and I support this agenda! *

  27. I donated as much to Sci Show through patreon as I paid for my tDCS device: 0$. Its about putting electricity through your body… not terribly expensive you know XD

  28. Hey everybody! I'm writing my thesis on the use of tDCS-devices.

    If you could please spend 3 minutes on my survey, it would be much appreciated!

    Thanks in advance!

  29. Respectable American institutions for some reason continue to study this, but why would they continue I guess is the more important questions. All the studies are online. It's been approved by the Netherlands government for medical treatments as well. I"m not saying it works, just check the facts. Gov makes more money from Adderall, Amordafinil and other drugs. I say follow the trail away from the money.

  30. Smart inclusion of the patreon note. This time it was actually tied to the subject in the video. And. Well. Got me actually thinking about helping the channel. I have a really tight budget, so i have to choose carefully what channels i give my money.
    The point i was making; The tDCS has no evidence of making me/you any smarter. Though, the SciShow already has. I usually google a lot of things mid-video, i get just the pointers on what to search for from these. And, some videos have taught me a lot.

  31. I'm looking into getting TMS therapy for severe deppression. It would be awesome if you guys could do a video on it. If it's anywhere near as effective as claimed it could completely change lives for people like me who have no choice but to suffer from and medicate severe clinical deppression

  32. What about the tDCS (I think it’s also called CES for cerebro electric stimulator) that have certain wavelengths (subdelta, delta, theta, gamma, etc.) Also, I saw this thing called ICES from a company from micropulse that uses strong magnetic fields instead of electricity.

  33. I remember making a tDCS device after I saw an episode of through the wormhole with Morgan Freeman back in late 2012. In the episode the technique was being tested for military application, and was showing that people under stimulation were significantly cutting learning curbs. They were performing at almost the same level as those that were experienced without having all the practice hours. I was trying to increase the activity in the right prefrontal lobe, and used it only a couple of times. I decided that the whole thing was still premature and I'd be better off waiting for proven research before I continued.

  34. Jim Carrey need TDcs It will bring him back If I can turn in him into the law more man I know how I no way I will bring forth The data

  35. For the naysayers, the current gets to the brain. You can get flashes of light when stimulating the occipital area with too much current. I have had very vivid dreams after using the device. Somewhat scary at times!

  36. You had your mind made up that electric brain stimulation creates no positive difference and you just went on that.

  37. You know what guys, previously I held your Channel is some notable, respect. However after this hatchet-job that you dis on tDCS AND pitch to spend the cash on your Patreon Support??? I have lost all respect for your content. It has no value whatsoever, BECAUSE you are already pre-biased in your treatment of your selected subjects. Poor showing indeed!

  38. Funny the commercial at end of video is from a drug company. tDCS could hurt the pharmaceutical industry so speaker slams tDCS. Paid off dude?

  39. This will never get any serious testing done because its a threat to big pharma industry. You can build your own device for about $10, vs a bunch of psych meds that will cost a ton of money, give you bad side effects and addiction and generally not work at all.

  40. TMS patient here with over 200 sessions. TDCS does work as long as you know where to put the electrodes, different placements of electrodes give different results. It's about 10% as effective as tms. TMS is much better than tdcs and ect. TDCS is a good when you know what you're doing or follow clinical trials.

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