
Study: Brain represents tools as temporary body parts - vaksel
http://www.scienceblog.com/cms/brain-represents-tools-temporary-body-parts-study-confirms-22536.html
======
patio11
Somewhat surprisingly, you can reproduce part of this result at your desk. (In
a hilariously non-controlled, do-not-quote-me manner.)

Rest your right arm on your desk with your palm facing upward. Touch the inner
side of your elbow and the tip of your middle finger, using your left hand. At
this point, I thought "Wow, my arm is longer than I would have expected it to
be."

Now, take a pen in your right hand and use it as a pointing device to follow
the words of this sentence. Still holding the pen, replace your right arm on
the table in the same position as you used before. Touch your inner elbow and
fingertip again. (At this point, my first thought was "Oh crikey it got
bigger." Its funny, I actually perceived extra stress in my left arm, as if I
were stretching to cover a distance that I had had no noticeable difficulty
with 15 seconds before.)

~~~
eru
Your description could use some figures. ;)

------
oPerrin
Old hat. The reverse is actually more interesting! The representation of the
brain is reflected in body parts. People think about the brain as being the
seat of neuroplasticity but your limbs are actually learning patterns, as are
your ears, your eyes. Anywhere there are neurons there is learning and memory.
This means that 1. sometimes reaction is faster than transmission to and from
the brain could allow for and 2. often input is filtered and enhanced before
it gets to the brain based on previous experience.

While it's cool to think that we "become one" with our tools, until they can
also form a part of this distributed memory grid they will always feel subtly
wrong, clumsy, and foreign.

~~~
TrevorJ
After time they really don't feel clumsy at all, that's what is amazing. To
get a grasp on just _how_ integrated a tool (Or better, a musical instrument)
gets, try using a common device with the opposite hand and feel how clumsy it
it feels in comparison. That's the natural pre-integrated state. Part of what
is happening is that the brain actually devotes more neurons to the hand that
is manipulating the tool. This probably makes up somewhat for the fact that
the tool itself has no sensing ability.

The mind map for the hands of professional piano players have many more
neurons devoted to the hands than in normal people for instance.

Classical guitar players use their fingernails to great effect when playing to
generate widely variable sounds depending on how they employ them. One could
argue that you fingernails function much as tools do in this case in the sense
that they don't have nerve endings at the tips but instead transmit feeling
through vibration down to the nail bed. The same thing is happening on a
larger scale when you hold a screwdriver, the resistance and vibration is
transmitted down to the hand which senses it. Over time more neurons get
devoted to those sensing and manipulating areas.

More info here: <http://health.howstuffworks.com/brain8.htm>

And here: <http://en.wikipedia.org/wiki/Sensory_homunculus>

------
GeneralMaximus
I would be interested in a similar study on how the mind perceives software.
The mouse pretty much seems like an extension of the body, but what about the
keyboard? I'm typing this message right now without even glancing down once at
my keyboard. How does that happen?

What about software that, over time, becomes "muscle memory"? Vim or Emacs,
for example. Or UNIX shell tools (grep, awk etc.). What about programming
languages? Sometimes I start thinking about problems in terms of whatever
programming language I happen to be using at the moment. When I work on a
project, I have a feeling of structure. I sometimes visualize OO code as
various compartments. How does that work?

------
theblackbox
When reading this all I could think about was Glamdring and the ancient's
insistence on the soul of a warrior being embedded somehow in their weapons.
I've always had a deep love of circus skills including Staff and Sword play,
and remapping my "physio-spatial" model is second nature. The eerie part is
when you can actually feel it happening, it feels like the sword/tool forces
it's way into your consideration. I can only imagine what it must have been
like for the blades and tools of old, with all their might and "magic"!!

------
10ren
Reminds me of body-controlled sports, like hang-gliding, snowboarding and
motorbike riding: the way the craft responds to body placement really makes it
feel like it is part of you.

I'm sure that this effect is separable from human intelligence, and tool-using
animals (like chimps using sticks and beavers building dams) feel the same
way, because it seems like the simplest way for the mind to integrate tools:
after all, a stick behaves as if it were an extension of your hand, so why not
reuse existing perceptual and motor control circuitry, rather than
constructing entirely new subsystems.

(I'm not saying it's designed, but reuse is more probable than parallel
reconstruction from scratch).

------
mlinsey
Heidegger vindicated at last!

~~~
omouse
Don't forget Marshall Mcluhan. He said tools and media were an extension of
man as well.

------
die_sekte
I wonder what kind of tools this covers. Only things like screwdrivers,
toothbrushes, or even things like cars?

~~~
arketyp
I would say, cars most definitely yes. And we should not only consider
concrete objects even. There's really no principal difference in the way we
learn to operate the character in a video game, or an internet browser, from
how we learn to walk with our legs and body - it's prediction and feedback
just thee same. That's the plasticity of the brain.

I think it's a little misleading to talk about "temporary body parts" however,
as if there are some distinct conditions for when a tool is like a part of
your body and when it's simply a tool we learn intimately.

"Woa, is this hand really a part of _me_??"

The neocortex really is an amazingly extended phenotype.

~~~
joeyo

      > there are some distinct conditions for when a tool
      > is like a part of your body and when it's simply a tool
      > we learn intimately.
    

Perhaps these are just different points along a continuum-- all tools (and
limbs) are integrated into the body schema to varying degrees. Consider that
dancers learn to exert far more exquisite control over their movements than
most people do. Another example: a large portion of strength training gains
are not simply due to muscle hypertrophy, but to the motor system learning how
to recruit the muscles in more coordinated and controlled ways.

Edit: On re-read, it looks like we are agreeing with each other. :-)

