Sep 20 2011

A Bit of Harmless Brain Stimulation

Will classrooms of the future be outfitted with devices that students wear over their heads to stimulate the brain and aid in learning? Well, it’s too early to tell, but a recent study suggests this might be plausible.

Prof Heidi Johansen-Berg and her team at Oxford have been conducting research into the effects of using a small electrical stimulation to the scalp in order to apply a small electrical current – using a transcranial direct current stimulation device (tDCS). (This is different from a transcranial magnetic simulation device, although the principle is the same.) They presented their findings at the British Science Festival in Bradford – I don’t see a published version so I have to go on the press reports.

They had been studying the effects of tDCS on stroke recovery. They found that when applied to the motor areas patients were able to relearn lost motor skill more quickly. They then applied the technique to healthy subjects. They gave them a task to memorize a certain sequence of button presses. They found that the stimulation increased the speed at which they learned the task. However it did not improve the best performance of the subjects.

The researchers speculate that the electrical stimulation may facilitate the changes that occur in neurons in the learning process – increasing dendritic connections, for example. This is an interesting concept. It’s not clear why this would be the case, but it is not implausible.  Perhaps there is also a non-specific effect going on, such as increasing attention.

Before we start applying this technique more research needs to be done. The basic effect itself needs to be confirmed through replication. In addition we need to test the long term effects of tDCS. It has already been demonstrated to be generally safe, but I wonder what the long term effects are on learning.  It’s important to recognize that maximal performance was not improved – so the technique does not seem to make people learn better, just faster. Does the learning, however, have the same staying power, or does it also fade faster? Is the effect sustainable, or does the brain develop tolerance to the effect. And are there other long term effects to using this technique.

As always I fear that with preliminary research into a new device like this one or more companies will decide to market a version of it and make direct clinical claims, before all the follow up research is done. If the idea that electrical stimulation aids learning gets out there, then we can likely expect to see a host of dubious products based upon this claim, many of which probably don’t even function (meaning they don’t produce the same level and precision of stimulation as used in the research).

I also like to think of where such technology can lead. It does seem likely that at some point in the not-so-distant future we will have the knowledge and technology to implant computer devices into brains routinely (we already implant electrodes for stimulation). These could then be used to deliver precise stimulation to networks and structures within the brain to potentially achieve a host of effects, both for disease treatment and general enhancement.

Right now there are three primary ways in which we alter brain function: The first is the traditional method – using the biological sensory inputs and motor feedback, i.e. therapy of one sort or another (traditional learning, talk therapy, physical therapy). The second method is pharmacological – increasing or decreasing the activity of various neurotransmitters.  The third is surgical – removing parts of the brain; for example, removing a seizure focus in order to decrease the frequency of seizures. We are at the dawn of adding a fourth modality – using electrical or magnetic stimulation to directly increase, decrease, or pace the activity of specific areas or networks in the brain.

This fourth modality may prove ultimately to be the most powerful and specific intervention. The brain is, at least partially, an electrical organ and this gives us the opportunity to directly alter brain activity using electrical or magnetic stimulation.

This type of intervention will benefit from advances in a few areas. The first is computer technology, which continues to advance quickly. Smaller, faster, and more energy efficient processors will be helpful – especially energy efficiency, not only because of the need for an energy supply, but also to minimize waste heat.

The second is miniaturized batteries or power cells. Researchers are working on technologies to capture energy from the body and use that to power small implantable devices. This approach is better than a battery.  Current battery technology is still highly limited, and it is not easy to recharge or replace an implanted battery, so any such battery would likely be placed outside the body, which has it’s own limitations. A device that can capture energy from the body, however, would be a continuous source of energy that never needs recharging.

The third area of research is the mapping of the brain itself – getting a more and more detailed map of the modules and networks in the brain and a better understanding of exactly what they do, and the effects of altering their function.

It’s extremely difficult (to the point of folly) to predict future technology. But perhaps we can glimpse broad brushstrokes. If so, I think it’s likely that this type of intervention will increase significantly in the future, and may largely replace pharmacological and surgical interventions.

16 responses so far

16 thoughts on “A Bit of Harmless Brain Stimulation”

  1. Bronze Dog says:

    Enhancing implants would be nice, but an external stimulation device would give me the excuse to say “Put on your thinking caps!”

    Personally, I’d be pretty nervous with the idea of putting implants in the most delicate part of me, but I could probably put aside that squeamishness. Of course, I’d be a late adopter in any case, since you neuro guys tend to bump into extra onion layers of complexity and interaction whenever you study an issue with the brain.

  2. tmac57 says:

    If the idea that electrical stimulation aids learning gets out there, then we can likely expect to see a host of dubious products based upon this claim, many of which probably don’t even function (meaning they don’t produce the same level and precision of stimulation as used in the research).

    While not directly referencing this study,there is a produce called Sota Bio Tuner BT-7 that implies that it may improve “…memory,creativity,learning and intelligence” through use of a Cranial Electric Stimulator which produces pulses of 500 frequencies.

  3. elmer mccurdy says:

    I recall about 10 years ago reading that about an experiment that showed some sort of electrical brain stimulation to improve drawing ability (of a dog) as well as performance on some sort of proofreading class, but I’ve never heard any more about it. It got me briefly thinking that it might be fun to try rigging something up with my TENS unit, but, like the song goes, something, something said, “You better not.”

  4. elmer mccurdy says:

    proofreading task, not class.

  5. tmac57 says:

    elmer- How much did the dog’s drawing ability improve?

  6. elmer mccurdy says:

    See, that’s the sort of thing that got me thinking about trying it.

  7. elmer mccurdy says:

    Anyways, here’s the 1st article about it from my google search:

  8. locutusbrg says:

    I am no Neurologist, but I think you kind of indicated the idea’s future usefulness with damning praise.. You went from ” might be plausible” to “It’s not clear why this would be the case, but it is not implausible. ” In two paragraphs.
    I think it would be better to say that this is an interesting idea that is not scientifically impossible but suspect. Very interesting to you personally. Could be you know this group does very good work and you are giving them the benefit of the doubt. Sound a little like electrical NLP to me.

  9. robm says:

    I can’t help wondering if the first place this would be used outside of medicine would be in sports to improve coordination and technique, brain doping essentially. There would always be some athletes who would be willing to take the risk, just like with current doping, and it would be harder to test for.

    As for brain implants, I can’t help but wonder about the risks (besides the obvious, like brain surgery), like what would happen in the event of a car crash or concussion, as well as exposure to electromagnetic fields and radiation.

    Not saying brain implants can’t be a useful treatment for injury or disease, only general brain enhancement might be the equivalent of using a pacemaker for heart overclocking.

  10. SARA says:

    I find this idea fascinating. Mostly because I suffer from depression and have never found a medication that works with any real effectiveness. My docs have tried all the obvious and a lot of the not obvious choices.

    I often think that my depression is similar to OCD. Its like my brain is stuck in a “depression state” mode and repeating a circular set of connections uselessly, rather than obeying my intentions of moving out the depressive behavior. I often imagine that if I could just reroute the current connections in my head to a new path I could move to a productive and healthy life.

    Perhaps this type of research will lead to that kind of help for people with depression, anxiety, OCD, etc.

  11. tmac57 says:

    SARA- That’s an interesting self observation about having OCD like
    behavior regarding depression. Someone close to me also obsesses about things that she cannot change,but finds it difficult to change her train of thought,and this is causing a long term depression.
    I personally have a kind of OCD thing which involves a nearly perpetual case of having different pieces of music run through my head at all times,(and I mean always).It’s bad enough just having the music there all the time,I can’t imagine how much worse it would be if it were depressive thoughts or mood.
    They do treat patients in my area using TMS,but I have not heard anything about what kind of efficacy it has.

  12. BillyJoe7 says:


    An old friend has that problem which she resolves by listening only to classical music. Classical music is too complex to keep running in her brain. And she avoids the radio like the plague.

  13. tmac57 says:

    BillyJoe7- Great! Now I have ‘Ode To Joy’ stuck in my head! 😉
    But seriously,I think I’ll give it a try. I really love music,but the only way I have found to avoid this is to go a week or more without hearing anything even remotely ‘catchy’. Even a TV jingle can set off a bout of this that can last a week or more.
    Maybe some Phillip Glass…?

  14. Xplodyncow says:


    Stagg CJ, Jayaram G, Pastor D, Kincses ZT, Matthews PM, Johansen-Berg H. Polarity and timing-dependent effects of transcranial direct current stimulation in explicit motor learning. Neuropsychologia. 2011 Apr;49(5):800-4. Epub 2011 Feb 16.

  15. Calli Arcale says:

    Smaller, faster, and more energy efficient processors will be helpful – especially energy efficiency, not only because of the need for an energy supply, but also to minimize waste heat.

    This immediately put me in mind of a person with wing-like vanes sticking out of their head as radiators. 😀

  16. Eric Thomson says:

    Cool, but caution is needed before we all run out and by a TCMS machine.

    One of the main animal models of epilepsy is the ‘kindling’ model in which epilepsy is induced in rats by stimulating for just one second (yes, second) a day with a single electrode.

    Just sayin’, stimulating your brain should be done with some caution, especially if the stimulus produces a lot of synchronous activity that the brain isn’t used to. It may maladaptively respond to the stimulus by becoming a permanently epileptic brain.

    Long shot, yes, just urging caution just like we show with alternative medicines.

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