Gödel, Escher, Bach An Eternal Golden Braid by Douglas R. Hofstadter

Motor areal Central sulcus

Auditory area

Cerebellum

Brain stem--~

F [GURE 66. The human brain, seen from the left side. It is strange that the visual area is in

the back of the head. [From Steven Rose, The Conscious Brain, updated ed. (New York: Vintage,

1966), p. 50.]

at this time be made between such large-scale suborgans and the activities,

mental or physical, which they are responsible for. For instance, it is known

that language is primarily handled in one of the two cerebral

hemispheres-in fact, usually the left hemisphere. Also, the cerebellum is the

place where trains of impulses are sent off to muscles to control motor

activity. But how these areas carry out their functions is still largely a

mystery.

Mappings between Brains

Now an extremely important question comes up here. If thinking does take

place in the brain, then how are two brains different from each other? How

is my brain different from yours? Certainly you do not think exactly as I do,

nor as anyone else does. But we all have the same anatomical divisions in

our brains. How far does this identity of brains extend? Does it go to the

neural level? Yes, if you look at animals on a low enough level of the

thinking-hierarchy-the lowly earthworm, for instance. The following

quote is from the neurophysiologist, David Hubel, speaking at a conference

on communication with extraterrestrial intelligence:

The number of nerve cells in an animal like a worm would be measured, I

suppose, in the thousands. One very interesting thing is that we may point to a

particular individual cell in a particular earthworm, and then identify the

same cell, the corresponding cell in another earthworm of the same species.'

Brains and Thoughts 341