Adult Brains Grow From Specialist Use

Xemu writes "Researchers at University College of London's Institute of Neurology have discovered that taxi drivers grow more brain cells in the area associated with memory. Dr Eleanor Maguire says, 'We believe the brain increased in gray matter volume because of the huge amount of data memorized.' She warns against the use of GPS and says it will possibly affect the brain changes seen in this study. This research is the first to show that the brains of adults can grow in response to specialist use." London cabbies, unlike their American counterparts, have to learn the layout of streets and the locations of thousands of places of interest in order to get a license.

Comments

Like every other muscle

[LiquidCoooled]

If you train it and work with it it will grow and remain strong.

My bulging typing fingers and keen google-foo are testament to that.

Re:Like every other muscle

[Average_Joe_Sixpack]

If you train it and work with it it will grow and remain strong.

My right arm and wrist are stronger than my left ... not sure how it ever got that way.

Re:Like every other muscle

[rolfwind]

Interesting you mention typing. I touch-typed with a regular QWERTY keyboard for at least 10 years, and two years back, I switched to the DVORAK layout. These days, people look at me in disbelief if they know I can program computers, but I start fumble with a regular keyboard. My muscle memory has completely changed over to dvorak and I can't type QWERTY worth a damn. I am a relatively quick learner (learned fluent dvorak by forcing it on myself in 8 hours of concentration) too.

My mother used to be fluent in French, being a translator. She hasn't used the language in 20 years. She has almost forgotten it completely as she can't make sentences so easily. (Though I am sure she can get back into it 100x faster than a newcomer).

It is almost like the brain is a muscle. After Terry Shiavo died, the autopsy found that her brain shrunk to the size of grapefruit.

I wonder if there is a correlation of speed of learning and speed of forgetting and the brains that "erase" (or shove aside) old info faster take in new information easier.

What about trivia nuts?

[khasim]

Does memorizing the names and stats of baseball players make your brain grow?

What about people who memorize every little detail of Star Trek?

Or is it that only people with the additional brain mass CAN memorize all those items?

Re:What about trivia nuts?

[HappySqurriel]

Or is it that only people with the additional brain mass CAN memorize all those items?

Trust me, memorization has very little to do with intelligence and more to do with exposure and motivation to memorize a subject ...

I honestly don't think it should be a surprise that working with an area of your brain would increase its "strength." This is (effectively) what practice is ...

Take any person who has never learned a musical instrument before and examine the impact of musical stimulus on their brain. Spend 8 hours a day for the next year teaching them musical theory and composition as well as several instruments and then examine the impact of musical stimulus on their brain. Being that they've practiced and learned a lot about music, one would expect that their brain would suddenly become far more involved in the musical experience.

At the same time, one of the questions of a study like this would be what would the consequence of television be on a person's brain? For the most part television would be training the brain in a way which would not be particularly useful in any pursuit and yet many/most people have a ton of exposure to this influence.

London cabbies...

[soliptic]

See The Knowledge and the references from there. I think it is only required for taxicab drivers (ie "Black cabs"), not minicab drivers.

Old news for nerds?

[the_humeister]

Studies were published in the year 2000. Why is this now getting attention? Actually, come to think of it, I think it got attention back then too.

Does this mean...

[Kiba Ruby]

Does this mean that programmers are more logical than people?

Cause or Effect?

[EmbeddedJanitor]

Do taxi drivers' brains expand to provide more memory, or do people with poor memory just forget to become taxi drivers?

A huge problem with any of these correlation studies is determining, accurately, which way the cause->effect relationship runs.

Re:Cause or Effect?

[slamb]

EmbeddedJanitor asked

Do taxi drivers' brains expand to provide more memory, or do people with poor memory just forget to become taxi drivers? A huge problem with any of these correlation studies is determining, accurately, which way the cause->effect relationship runs.

A good question, but RTFA:

Dr Maguire said: "We are now looking at the brains of taxi-drivers before they start training, and at those of retired cabbies to see whether that area of the brain gets smaller when it is not used."

Hopefully they'll actually follow the pre-training drivers through all the way through training so they don't compare future wash-outs with present successful cabbies rather than future successful cabbies with present successful cabbies. If so, it should go a long way toward answering your question.

The ultimate would be to compare the same population of cabbies vs. bus drivers (control group) through their entire careers. Obviously that'd be a long-term study, and it will become impossible when "the Knowledge" is obsoleted by GPS mapping software. (I say "when" rather than "if". It will happen sooner or later.)

Re:Cause or Effect?

[timeOday]

I'm surprised they even bothered if it's not a longitudinal study. "This just in, basketball makes you taller. Those who give up on basketball don't develop legs as long as those who stay with it throughout professional basketball careers."

Re:Cause or Effect?

[slamb]

There seems to be an assumption that people won't learn what they don't "have to" learn (I've heard this argument against PDAs too). But maybe people just learn what they're repeatedly exposed to, or things with emotional connections. Technology may or may not interfere with that. It's not a question I would guess at the answer without some evidence either way.

I generalized from similar observations:

• Now that I have a cell phone with a good phonebook, I no longer memorize phone numbers. (I remember phone numbers I called 10 years ago, but I don't remember phone numbers I now call all the time. There's no need.)
• Now that cashiers have cash registers, they no longer do basic arithmetic. (Sadly, most don't even remember how to do the arithmetic. They were all instructed in elementary school, but it didn't stick...)
• Now that cashiers have bar code scanners, they no longer remember prices. (But they do remember the typed codes for fruit and vegetables.)
• Now that I have Eclipse toolhints, I no longer remember Java library functions' argument orders.
• ...

In general, it seems that when it's more convenient and about as effective to use a machine as to do something by hand, people will no longer take the effort to do it themselves. And memorization (of prices, phone numbers, street names, anything) is way harder for people than for computers.

If the software works well enough that cabbies can reliably enter an address and find the street, why should cabbies be made to remember all the street names? And if it works so well that it can reliably pick an optimal route (including traffic, construction, etc.) why should they even remember how to get anywhere?

In fact, I predict they'll start depending on it before it's reliable. The test will go away, and for better or for worse, there will be a lot more cabbies out there, and they won't be able to get around very well when the computer acts up, just like a lot of businesses now can barely sell anything when their cash registers act up. It will be a pain to get to certain streets because the database is wrong, and cabbies will unknowingly avoid certain more optimal turns/intersections because the software can't navigate through them.

Re:Cause or Effect?

[dirgotronix]

I'm a cabbie.

I was in a motorcycle accident in 2001 which caused serious short-term memory issues in my brain. I started driving a cab in february of 2006, and I have noticed an increase in my short term memory.

When I first started, I would have to ask my passengers to give me directions one turn at a time (and in my mind, I was repeating that single direction) in order to get to the destination. Now, I can generally get anywhere on address alone, or, at a minimum, remember the address all the way through the trip, despite having various conversations, remembering turn by turn directions, avoiding accidents, etc.

I'd say I agree with the studies, from personal experience.

Re:How do they know?

[zCyl]

Did these scientists have a "control experiment" done? The very usage of the word "believe" scares me. That means that there could be another scientist who might *not* believe.

Welcome to the real world of science, where conclusions are not solid, facts are not certain, and evidence is only an indication. :)

Re:How do they know?

[niconorsk]

From TFA:

In the study, researchers at the Wellcome Trust Centre for Neuroimaging at UCL's Institute of Neurology carried out scans on the brains of 35 cabbies and bus drivers, all men. Various psychological tests were also carried out. Using bus drivers meant that any brain differences found could not be explained by driving stress, or dealing with passengers and traffic in London. The one big difference between the two is that bus drivers stick to routes, while cabbies have to learn the layout of streets and the locations of thousands of places of interest to get an operating licence. So clearly they had thought of that particular possibility. What concerns me though, is how they know that their brain matter has grown rather than just having large memory centers from the start. They should probably do the same experiment with cabbies preparing for their exam and take the measure before and after.

It's true

[Tablizer]

I've found my Bullshit Lobe doubling in size since I entered the corporate world.

Re:london streets

[gilgongo]

One side effect of London cabbies having to do "The Knowledge" to get a license is that it creates a market for cheap, illegal cab drivers to fill the supply gap brough about by having such an exclusive system. With hoards of unlicensed cabbies around, women get raped, uninsured road accidents happen, tourists get ripped off and legitimate cab fares are sky high.

I am a Londoner, and I think the sooner the GPS makes The Knowledge a prerequisite of licenced cab driving irrelevant, the better. The times I've been to NYC and got a cab it's been paradise in comparison.

Plato/Socrates said that about writing too...

[KarmaRundi]

"Soc. At the Egyptian city of Naucratis, there was a famous old god, whose name was Theuth; the bird which is called the Ibis is sacred to him, and he was the inventor of many arts, such as arithmetic and calculation and geometry and astronomy and draughts and dice, but his great discovery was the use of letters. Now in those days the god Thamus was the king of the whole country of Egypt; and he dwelt in that great city of Upper Egypt which the Hellenes call Egyptian Thebes, and the god himself is called by them Ammon. To him came Theuth and showed his inventions, desiring that the other Egyptians might be allowed to have the benefit of them; he enumerated them, and Thamus enquired about their several uses, and praised some of them and censured others, as he approved or disapproved of them. It would take a long time to repeat all that Thamus said to Theuth in praise or blame of the various arts. But when they came to letters, This, said Theuth, will make the Egyptians wiser and give them better memories; it is a specific both for the memory and for the wit. Thamus replied: O most ingenious Theuth, the parent or inventor of an art is not always the best judge of the utility or inutility of his own inventions to the users of them. And in this instance, you who are the father of letters, from a paternal love of your own children have been led to attribute to them a quality which they cannot have; for this discovery of yours will create forgetfulness in the learners' souls, because they will not use their memories; they will trust to the external written characters and not remember of themselves. The specific which you have discovered is an aid not to memory, but to reminiscence, and you give your disciples not truth, but only the semblance of truth; they will be hearers of many things and will have learned nothing; they will appear to be omniscient and will generally know nothing; they will be tiresome company, having the show of wisdom without the reality." Translation nabbed from here

Bet he would have hated Google. All we have to remember now is how to use it and a few key words.

London cabbies vs American cabbies

[56ker]

London cab driver (visiting my mum's cousin):-

No map required, took us directly to the street - no problems - good tip

American cab driver (picked me up from Dallas Fort Worth airport)

Said he "used to live there", had a map - was only 6 miles from the airport but he managed to get lost, take about an hour or two to get there (had this insistence he must drop me off at the correct number) and ended up charging less than what was on his meter out of embarrassment.

So, yes I'll take a London cab driver (or walking/public transport if I'm in America) vs their American equivalent any day of the week. :)

Use a GPS. Save your brain for something better.

[cvd6262]

Recommending that GPS units shouldn't be used because it would cause a change in the person's brain is ridiculous unless the benefit of *not* changing the brain is good for anything other than the task the GPS does.

American Scientist had an episode where they taught a seeing girl braille, and tested her ability while doing an fMRI. The sections of her brain that fired during the test were associated with tactile processing. Then they blindfolded her for 100 hours, and retested. This time, her visual cortex was firing. The brain is dynamic and can repurpose unused neurons. This may be why people can no longer remember 7-digit telephone numbers: We all have PDA/cell phones to do it for us.

Is this bad? Not unless you value the ability to remember phone numbers.

Would it be bad if London taxi drivers no longer knew every little alleyway? Not so long as they could still accomplish their task.

BTW, I had a very different experience with a cabby in Paris. I told him where I wanted to go and he handed me a road atlas and said, "Trouvez-le."

Spatial aspect is important

[dfedfe]

Well, the reason they looked at London cab drivers is because of the massive amount of spatial information they have to know. The hippocampus was first shown to be involved in spatial memory in rats in the '70s (if memory serves), though it is also known to be involved in episodic memory.

The original idea was that the hippocampus holds a map of spatial environments, and so if someone has a very large amount of spatial knowledge, maybe their hippocampal anatomy will reflect that. This hypothesis is supported by this evidence (that lab has been doing these studies for years, not sure why this is claimed to be so new, except perhaps the control subjects who were bus drivers in London, reducing one potential confound). It should be noted that lately it has been shown that there is a very robust spatial code outside of the hippocampus (and feeding into it) so it appears to not be quite as simple as the hippocampus just holding a map.

Now to your questions. Names, stats, and details are semantic memory, not episodic memory, and are therefore not directly related to the hippocampus (except that all semantic memory appears to start off as episodic memorys, which are slowly re-coded, if you like, into just memory of the facts and not the specific episode where you learned the facts). So if you were constantly learning large amounts of new such data, perhaps you'd see such growth in the hippocampus, but merely having it all memorized would be relying on storage out in neocortex, not the hippocampus.

As the hippocampus (specifically the dentate gyrus, one part of it) is one of the few regions known to constantly be producing new cells, it is expected that experience might cause changes in size there. In other parts of cortex it would be more surprising (to me, at least) if there was a significant change in number of neurons. There the changes are more likely to be structural: neurons making new connections with other, existing neurons.

In summary:
hippocampus = spatial information and acquisition of new memories
neocortex = use and storage of existing knowledge

It's not jingoism when it's true...

[Space cowboy]

I lived in London for 15 years (I now live in the USA). I've got into a cab in London and asked for a road 30 miles away, the guy not only gets me there without asking me for directions, he takes me down tiny narrow streets that avoid the traffic.

Compare this to my experiences in the USA:

- Wanting to get back to my hotel in Sausalito from San Francisco. I'm standing on Lombard (which turns into the Golden gate bridge, the best way to go) and hail a cab. He turns (right) onto a side-street, turns left, turns left, crosses Lombard again, turns right, turns right, crosses Lombard again, etc. He's being told how to get to Sausalito by his controller (I can *hear* his controller saying "turn onto Lombard" at which point he says "I've just crossed Lombard"). This goes on until I lean over and tell him I can direct him.

- Getting off a plane at Newark, having the rest of the day free before a plane home to the UK the next day. Ask cabbie to take me to the Empire State building - hell why not. He doesn't know where it is. I direct him to roughly the right area, and he says "this is as close as I can get". WTF ? Walking about 8 blocks (diagonally) I get to the ESB...

I could go on. In my experience, cabbies in London are top-notch. The only place I've found that has vaguely-similar cabbies is Las Vegas, and I've travelled a fair amount in the US.

Simon.

Where the streets have TOO MANY names.

[The Monster]

Aren't American roads in the large cities laid out in grids anyway?

The older a city is, the less true this is. In a city like Boston, there are neighborhoods with local grids at roughly the same granularity as those in London, and the same tendency of a road passing through an intersection to change names and reset numbering back to 1. Even Manhattan Island, the stereotypical grid of numbered Streets and Avenues, has them laid out according to the general orientation of the island, rather than the points of a compass

By contrast, Washington, DC was carefully planned, with a Cartesian quadrant system of N/S and E/W 'Streets' numbered from the Capitol building, as well as 'Avenues' that run at odd angles to that grid. The Public Land Survey System, which was used for the territories gained/defined after the US became independent of Britain, imposes a compass grid that largely governs newer areas, such as Florida and Western states.

It is often said that St. Louis (built long before the survey system) is the westernmost 'eastern' city, and Kansas City the easternmost 'western' city. A comparison of the two shows that the former indeed has virtually no streets that align with the compass, while the latter has most major roads aligned with the survey grids, right down to the streets across the state line not being quite exactly aligned (due to accumulated errors over the distances from the 5th and 6th Principal Meridians, from which the surveys were conducted).

The reason why London cabbies have to learn so many different street names is because there's so damned many of them, and no particular scheme to tie them together.

Re:So how does this explain George Bush ?

[Nefarious Wheel]

Gerald Ford was inept, not stupid, and he inherited the job. He made at least decent one pun* during his tenure, which puts him above average; modern US presidential candidates generally display less wit than Jay Leno.

Sometimes vice-presidents are chosen for their intelligence, which I believe is a ploy to keep them from competing for the top spot.

*("I think you're guilty of putting Descartes before TerHorst")