Originally posted by Deano
how does your mind work?!
Mechanically or conceptually? A subway system works mechanically by
cars on steel wheels, rails, and 500 volts of electricity shunted hither
and yon on overhead wires. Conceptually though it's a widget to get folks
from where they live to where they work, and it works by figuring out the
paths they take, assigning trains to those routes, and discounting fares
off-peak to even out the rush-hour crowds.
Mechanically the brain is billions of cells called neurons that can
produce little bursts of electricity that can be passed from cell to cell.
(Brain neurons are densely interconnected.) These bursts produce weak
electric fields at the surface of the head that can be recorded, hence the
EEG ("electro-encephalogram", Greek for recording (gram) of head (cephalus)
electricity, aha.) Coarse features in the EEG are found to be related to
broad categories of brain activity: larger, slowly-varying electric fields
indicate sleep, smaller, faster-varying fields alertness, etc. More subtle
measurements map increased electrical activity in certain *regions* of the
brain when people remember, speak, or blow their nose, and direct
electrical stimulation of certain areas of exposed brains produces
sensations, movement, memories of the Kennedy Administration, etc. Thus
the wide assumption is that it is the pattern of the electrical bursts of
the neurons that constitute thought, along with perhaps chemical changes in
each neuron to account for memory, learning, personality and other
slowly-changing brain behavior. An article in the April 1994 issue of
"Scientific American" details some recent nifty experiments on mapping
brain activity and correlating action and thought. Also consider the books
of Oliver Sacks on brain dysfunction.
You'd think knowing how the brain works mechanically would tell you
ipso facto how it works conceptually. Alas no. Conceptual understanding of
brain function is much more incomplete. Doubtlessly the most influential
thought on thought (argh), and a major force shaping social currents in the
20th century, is the hypothesis of the division into conscious and
unconscious mind. Much is known about learning and problem-solving
techniques of the conscious mind, and its organization of basic thinking
tasks (e.g. remembering, planning, perception), but we don't know the
mechanics of, and cannot duplicate ourselves, the two most outstanding
features of the mind: its ability to respond originally, i.e. create, and
its self-awareness, i.e. consciousness. For amusing essays on the latter
consider "The Mind's I" by Daniel Dennett and Douglas Hofstadter, or the
short stories of Stanislaw Lem. One of the most popularly influential
recent books is Julian Jaynes' "The Origin of Consciousness in the
Breakdown of the Bicameral Mind," which has left us with left- and right-
brainedness on the brain. My favorite paradigm is that *intelligence*
consists of having a mental model of the world in which to try out new
ideas for future action off-line (which as Karl Popper says enables
"our hypotheses to die in our stead"
, while *consciousness* consists of
including in that mental model a little model of *ourselves* as well. To
be conscious is then to be able to watch yourself watch the world. Yow.
Christopher Grayce
