Mind

The mind is a subject about which very much theorizing, experimenting, and
expostulating has occurred in philosophy (studied under the heading
philosophy of mind), psychology, and religion (where in theology it is often
considered alongside such related notions as soul and spirit). Some people
think it is synomous with the brain.

Substance or bundle?

There is a popular problem in philosophy about what the mind is, which can
be presented as follows. It is commonplace to wonder what the mind, or soul
(if you will), is. One can identify individual thoughts, individual
feelings, in one's mind. But what is this mind that has these thoughts and
feelings? One can imagine all sorts of mental goings-on, but what is it to
imagine the mind itself? It seems the only way we have of understanding, by
introspection, what our minds are is by considering various particular
thoughts, feelings, decisions, and other events in our minds (i.e., mental events).

So, someone might boldly maintain that we really do not have a mind, or a
soul, per se--at least, we do not have any mind or soul that is distinct
from our thoughts, perceptions, and other mental events. All there are is a
series of thoughts and feelings that are associated with our bodies. There
are no minds that are something over and above these thoughts and feelings.
This would be the view of someone who held a bundle theory about the mind.
The Scottish philosopher David Hume held a theory of mind like this.

The view of common sense, it seems, is opposed to a bundle theory of the
mind. We seem to have a mind, or soul, which is distinct from our thoughts
and feelings--and that mind is just exactly what we call our selves. Hume
seems to want to deny that there is such a thing as the self. To some people
this seems absurd. To them, a substance theory of mind will seem more
attractive. On this view, one holds that there is something--one may not
know what, but something--which has the thoughts and feelings, and the
thoughts and feelings are in our minds, in about the same way that
properties inhere in a substance.

Philosophers have not infrequently bandied the phrase "mental substance,"
and indeed, it has been made central to the ontologies of several
philosophers, including most notably Gottfried Leibniz; according to
Leibniz, the monad, a "simple soul," is that in terms of which everything
else in the universe was to be explained. The notion of mental substance is
also basic to the dualism of Rene Descartes. David Hume was very famous for
advocating a bundle theory of mind.

Psychological Experiments on Mind-Body relations

In a study patients were asked to flex the index finger of their right hand
suddenly at various times of their own choosing while the electrical signals
in their brain were being recorded on an EEG. It was found that there was a
gradual build-up of recorded electric potential for a second or a second and
a half before the finger was actually flexed, indicating that the
unconscious mind had made the decision before the conscious mind decided to
act. Or, the actual initiation of volition may have begun earlier in some
other part of the brain.

In another experiment on patients undergoing brain surgery, it took about
half a second to register a stimulus applied to the skin, despite the fact
that the brain would have received the signal of the stimulus in about a
hundredth of a second and the pre-programmed reflex response takes only
about the tenth of a second.