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The Science of Mental Fitness

Article #346 • Written by Marisa Brook

It’s a testament to the strength and versatility of the human brain that anyone with at least half of one tends to assume that their senses give them direct access to objective reality. The truth is less straightforward and much more likely to induce existential crises: the senses do not actually provide the brain with a multifaceted description of the outside world. All that the brain has to work with are imperfect incoming electrical impulses announcing that things are happening. It is then the job of neurons to rapidly interpret these signals as well as they can, and suggest how to react.

This neurological system has done a pretty good job of modelling the world such that the ancestors of modern human beings avoided getting eaten by sabre-toothed tigers before procreating, but the human brain remains relatively easy to fool. Optical illusions, dreams, hallucinations, altered states of consciousness, and the placebo effect are just a handful of familiar cases where what the brain perceives does not correspond to whatever is actually occurring. The formation of a coherent model of the world often relies on imagined components. As it turns out, this pseudo-reality in one’s imagination can be so convincing that it can have unexpected effects on the physical body.

Back in the 1980s, the future of computing--and pretty much everything else--was thought to lie in virtual reality. Although few modern homes actually contain immersive, multi-sensory 3D virtual reality machines, some devices along these lines can be found in medical facilities. Virtual reality therapy (VRT) has often targeted neuropsychological conditions such as phobias and post-traumatic stress disorder; however, since everything we experience has a lot to do with the brain, the range of the potential applications of VRT is much wider than this.

One creative use of VRT has come out of the University of Washington in Seattle, where researchers Hunter Hoffman, David Patterson, and Sam Sharar have been employing VRT since 1996 to address the excruciating pain of severe burn victims. Pain is a neurological response that is very sensitive to psychological factors. For instance, pain is particularly susceptible to the placebo effect, which depends merely on the expectation that a particular treatment will work. Burn victims frequently have flashbacks to the scenes of their accidents, and this intensifies their discomfort. The novel insight of the Seattle researchers has been that these patients experience much less pain from their burns if they imagine being cold. To that end, the researchers have collaborated on a virtual reality game called SnowWorld in which the player uses a headset and joystick to explore glaciers and icy caves full of animated snowmen, penguins, snowballs, and so on. Particularly during wound care--for instance, when bandages are being replaced--patients have reported substantially less pain and preoccupation with their burns while playing SnowWorld than while playing everyday Nintendo 64 games. In other words, SnowWorld owes its effectiveness not simply to being a distraction from the pain, but to convincing the brain that whatever heat it senses from the replay of the burn experience is being nullified by the cold suggested by the virtual environment. Studies based on functional MRI (fMRI) imaging are also beginning to show evidence for the utility of virtual reality in providing relief from pain.


In fact, mental exercises of all kinds--not just those supported by persuasive video games--can have a considerable effect on brain activity. One example is a type of mental arithmetic practised in Japan. Physical abacuses--counting devices relying on rows of beads--are common in the country, but a valued skill is anzan, or quick and accurate calculation by means of a mental abacus. Anzan propelled 22-year-old Naofumi Ogasawara to first place at the 2012 Mental Calculation World Cup in Germany. It is also featured in a competition called ‘Flash Anzan’, in which fifteen three-digit numbers are rapidly flashed on a screen and participants use mental abacuses to add them up. Using these imagination-based calculating tools, the most skilled participants can sum fifteen three-digit decimals in less than two seconds. Contestants begin using the mental abacus so immediately that afterwards they cannot remember any of the individual three-digit numbers.

Skills that can rely on mental practise are also familiar to those who need to practise physical motions regularly, such as musicians and athletes. For instrumentalists, having an actual instrument to play is pretty handy, but it turns out that having a mental copy of one can be almost as good. The musical community in general has been aware of this for decades or more. Noted pianists Vladimir Horowitz and Arthur Rubinstein both employed the technique of mental rehearsal--playing pieces on an imaginary piano in their minds--and for different reasons. Horowitz was uncomfortable practising on any piano other than his favourite Steinway; Rubinstein simply disliked spending hours at a time sitting at a physical piano. A similar story is recounted by Matthew and Sandra Blakeslee in their 2007 book The Body Has a Mind of Its Own: a violinist spent seven years in jail without his instrument, but practised mentally every single night. On the very night he was released, the violinist gave an impeccable real performance on his violin. The imaginary motions that the violinist engaged in during his stint in jail were able to build, or at least maintain, his fine motor skills.

These days, neuroscience is beginning to catch up to musicians who practise mentally. Although the details are still somewhat elusive, the key to the success of mental imagery as a rehearsal technique is that most of the same neurological regions are invoked by mental practise as by real practise. Research led by Alvaro Pascual-Leone of Harvard Medical School has found that this is true even in individuals who do not have prior musical training. Pascual-Leone and his associates taught two groups of non-musicians a basic finger exercise on the piano keyboard; they then had one group practise in the ordinary way and the other practise in their minds, for two hours per day, five days in a row. At the end of the study, the mapping of the rehearsal pattern in the brains of participants from both groups had changed in the same ways. Essentially, the brain can only barely tell the difference; a strong mental simulation of motion is, neurologically speaking, an excellent substitute for the counterpart real motion. Data from a 2004 fMRI study conducted by a team of researchers in Germany corroborates this conclusion; while activation is indisputably stronger and a little more widespread during actual music performance, mental rehearsal covers most of the same basic ground. This finding adheres to a general pattern that imagining a given action or sensation is likely to be neurologically analogous to physically carrying out that action or experiencing that particular stimulus.

A comparison of the frontal and parietal activation in music performance (left) and music imagery (right)
A comparison of the frontal and parietal activation in music performance (left) and music imagery (right)

Very similar, but even more striking, is the evidence from athletic training. As with rehearsing a piece on the piano, practising a complex physical task in the mind alone is nearly as effective a learning strategy as actually physically doing it. But it doesn’t stop there. In a 2004 study, a group of researchers from the Cleveland Clinic Foundation decided to find out whether mental practise of a minor exercise routine could actually result in physical changes to the target areas of the body. One group of subjects performed a regular exercise involving moving a finger sideways; a second group regularly imagined doing the same exercise but did not go through the physical motions; and a third (control) group did nothing unusual with their fingers at all. After 12 weeks of training, the physical finger-workout group showed an increase of 53% in finger strength; the control group did not show any changes in finger strength; and the mental-finger-stretching group showed an increase of 35%. In other words, the mental-exercise group physically increased the strength of one of their fingers by imagining, repeatedly, over the course of about three months, that they were exercising it. They didn’t have to lift a finger in order to convince their brains that they were, in fact, lifting a finger.

This result is not unique. A 2007 Canadian study targeting hip muscles had the same outcome: a group of college students using weightlifting increased their hip-muscle strength by 28.3%, a control-group doing nothing to their hip muscles exhibited no change in strength, and a group working on the muscles only via mental imagery showed an increase in the strength of those muscles by 23.7%. What this means is that imagining was almost as good as going to the gym, and probably cheaper as well. One can lie on the couch and build muscle just by thinking about doing those 200 push-ups or running those five kilometres, as long as one is careful and thorough.

Neuroscientists are still working on the enigma of why this might be. Clearly the brain has been tricked--motor neurons in the brain are receiving enough of a signal from the mental exercise to send out their minions to strengthen muscles--but the details are currently somewhat nebulous. Nonetheless, it is clear that the human imagination alone is capable of doing things that are certainly more than imaginary in their results. For that reason, anyone who has found the above insights to be “mind-blowing” are cautioned against repeatedly envisioning a literal take on this description.

Article written by Marisa Brook, published on 13 November 2012. Marisa lives in Toronto, Canada. She collects postcards, fridge magnets, lapel pins, interesting rocks, and linguistics degrees.

Podcast sound design by Alan Bellows. Podcast narration by Simon Whistler. Edited by Alan Bellows.

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Posted 13 November 2012 at 08:16 am

I knew the gym was a waste of time. Im gonna sit on the sofa and think me up some muscles

Posted 13 November 2012 at 08:30 am

Hmm. New meaning for jogging one's memory.

Posted 13 November 2012 at 10:30 am

I really wonder if this could be used to combat America's obesity epidemic. If people are unwilling to get up and move, would imagining getting up and moving be enough?

Also, I bet this explains why Wii Fit was so popular among old people.

Posted 14 November 2012 at 12:42 am

I totally learned to type this way when I was a kid. This was a long time ago, and neither computer keyboards nor typewriters were so readily available; I was taking a typing class, but it only met for an hour a day. I remember spending many, many hours a day for a couple of weeks mentally typing things I saw: road signs, cereal boxes, etc--I had dreams about typing things. IMHO all this greatly sped up the rate at which I improved my typing speed and accuracy.

Definitely a DI article.

Eloquent Rambler
Posted 14 November 2012 at 03:43 am

All this just makes me think of the Matrix. If you can imagine learning the piano, why not have a computer tell you that you've learned the piano in the same way, only alot quicker.

"I know Kung Fu"
"Show me!"

Posted 16 November 2012 at 12:09 am

Ya got trouble, my friend, right here, I say, trouble right here in River City! Evidently the solution really is the "think system".

Watch your thoughts for they become words. Watch your words for they become actions. Watch your actions for they become...habits. Watch your habits, for they become your character. And watch your character, for it becomes your destiny! What we think we become. (Iron Lady, The)

Posted 16 November 2012 at 02:13 am

Interesting article. But how was it possible to misspell "practice" so many times? No spell check?

Posted 16 November 2012 at 04:54 am

Hi Tod

Whether we like it or not, much of our language is now heavily influenced by American English spellings. We use both forms in British English

Alan Bellows
Posted 16 November 2012 at 07:03 am

Tod said: "Interesting article. But how was it possible to misspell “practice” so many times? No spell check?"

The Damn Interesting authors are an international gaggle. Marisa is from Canada, where "practise" is the appropriate spelling.

Marisa Brook
Posted 16 November 2012 at 10:55 am

Heh. Canadian English spelling is a real mixed-bag of American and British and idiosyncratic. Lots of variation, and different style-guides recommend different things. It's kind of all-over-the-place. While I was living in the United States, I tried to make sure to use American spellings in my schoolwork and DI articles, but even then I didn't always catch all of them. Heh. Some sources say that in Canadian English 'practice' is the noun and 'practise' is the verb, but I doubt it's that clear-cut for a lot of people up here. For some reason I've always spelled both of them 'practise'. Same with 'license'. It must just have been how I was taught. Regardless, sorry for the distraction!

(When I'm not writing for DI, I'm a Ph.D. student in sociolinguistics and dialectology and that sort of thing, so I could go on about English dialects all day. However, as that would probably be Damn Interesting only for me, I'll stop here.)

Posted 18 November 2012 at 08:33 pm

Should be slightly careful with the gym result. The paper reports a 20-30 percent gain over a two week period for both mental and physical result group. This type of gain is typical of a person who has begun targetted weight training of a muscle group/movement for the first time.

For those of you who do go to the gym, you'll probably recall the rapid gains during the first few weeks, followed by a dramatic slow down. It's pretty much accepted now that most of the strength gains during this initial period is the result of neurological factors - that is your body/mind learning how to actually move in an effective way. It takes several weeks for your body to begin actually increasing muscle mass.

This is important because it suggests that the test result may only be valid for the initial gains phase.

Posted 19 November 2012 at 01:41 am

Thank god I waited forever. Notice there isn't a comma in there. :D

Keep the brilliant articles coming!!!

Posted 19 November 2012 at 06:30 am

It sounds as if the test subjects focused intensively to get the result they did. So I definitely echo Ms. (or Mrs) Brook in saying you should take caution in an imaginary use of exercise.

I myself cannot go more than 30 seconds before my mind completely switches topics... what was I talking about? :P

Posted 19 November 2012 at 06:40 pm

Ohhh yeah!! Lov this article. There is a lot of these in Metaphisics. What u think, what u feel and what its manifest is always a match!! If you r intrested on these u should see the movie "What a Bleep do we know??"
A beg your pardon if I misspell some words, english is not my mother languaje!
Good life 4 you all!!

Posted 14 December 2012 at 01:43 pm

Many years ago, I remember reading something similar about people who practiced playing soccer versus people who just thought about practicing soccer with similar results. I'm glad that this story is consistent as I was starting to think it was a one-off go nowhere type of study.

But what is the real application her? The brain, when imagining an activity, sends impulses to the muscles to make them bulk up? Can I get a brain implant that will do that for me so that I don't have to spend two hours a day thinking about lifting weights?

Does that mean that when I do lift weights, I'd be better off thinking about the weights that I'm lifting instead of my current habit of listening to music on my headphones?

Posted 24 December 2012 at 12:11 pm

DI. Thanks, Marisa.

Posted 06 January 2013 at 11:36 am

I never gave up on this site! Great article.

Posted 15 February 2013 at 08:45 pm

Even better if one can harness the old wish-for-more-wishes trick. As in, thinking about doing stuff makes you better at it - so, what does a thinking man do, he thinks about thinking.

e.g. if he had 2 years to mentally work out, he should spend the first year thinking up about thinking, and the second year thinking about working out. That way he'd end up with quadruple the muscles he'd have gotten through mental working out alone, based on all existing measurements.

Point proven.


Posted 16 August 2013 at 08:53 am

well , the obvious here that's left out is that when we think about someone/thing attractive, we get aroused physically.
Posted 12 September 2014 at 07:32 pm

My 5years old son can do maths mentally just how this article describing the japanese contestant. Its a learnt skill and its amazing seeing him give out answer in a few seconds after his teacher verbally dictate the numbers. Sorry. Im a proud mother that just wanted to rave about him for abit. DI article!!! Thanks!

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