Brian Capacity

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

Kalman Rubinson (kr4 at 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:

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.

The whole  book can be found at
and should be read by anyone who cares enough to post questions about brain
usage on this newsgroup. 


Didier A Depireux                              didier at
Neural Systems Lab       
Institute for Systems Research          Phone: 301-405-6557 (off)
University of Maryland                                -6596 (lab)
College Park MD 20742 USA                     Fax: 1-301-314-9920

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