# Brian Capacity

Didier A. Depireux didier at Glue.umd.edu
Mon May 24 09:05:13 EST 1999

Kalman Rubinson (kr4 at is2.nyu.edu) wrote:

: While I agree with you that it is extremely unlikely that we use only 1%
: of our brains and that it is unfortunate that this probable fallacy is so
: commonly accepted but your argument proves nothing. What if the subject 1%
: were distributed throughout the entire mass?

As I did the last time this very question was asked, I will quote from
"Conversation with Neil's brain", written by William Calvin:

\begin{quote}
Indeed, this is the origin of that dubious factoid: "You use only 20
percent of your brain anyway." This is true, but only in a very limited
sense. Before the hand starts acting weak or paralyzed, a slowly growing
tumor has to kill about 80 percent of the cells in the hand region of
the motor strip. Yet that is a very crude test of function. A pianist or
mechanic would probably notice problems long before then. And a stroke
that suddenly killed perhaps 30 percent of the neurons in the motor strip
would also cause paralysis.
\end{quote}

The whole  book can be found at
http://weber.u.washington.edu:80/~wcalvin/bk7/bk7.htm
and should be read by anyone who cares enough to post questions about brain
usage on this newsgroup.

Didier

--
Didier A Depireux                              didier at isr.umd.edu
Neural Systems Lab                 http://www.isr.umd.edu/~didier
Institute for Systems Research          Phone: 301-405-6557 (off)
University of Maryland                                -6596 (lab)
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