physicsworld | Consciousness appears to arise naturally as a result of a brain
maximizing its information content. So says a group of scientists in
Canada and France, which has studied how the electrical activity in
people's brains varies according to individuals' conscious states. The
researchers find that normal waking states are associated with maximum
values of what they call a brain's "entropy".
Statistical mechanics is very good at explaining the macroscopic
thermodynamic properties of physical systems in terms of the behaviour
of those systems' microscopic constituent particles. Emboldened by this
success, physicists have increasingly been trying to do a similar thing
with the brain: namely, using statistical mechanics to model networks of
neurons. Key to this has been the study of synchronization – how the
electrical activity of one set of neurons can oscillate in phase with
that of another set. Synchronization in turn implies that those sets of
neurons are physically tied to one another, just as oscillating physical
systems, such as pendulums, become synchronized when they are connected
together.
The latest work stems from the observation that consciousness, or at
least the proper functioning of brains, is associated not with high or
even low degrees of synchronicity between neurons but by middling
amounts. Jose Luis Perez Velazquez,
a biochemist at the University of Toronto, and colleagues hypothesized
that what is maximized during consciousness is not connectivity itself
but the number of different ways that a certain degree of connectivity
can be achieved.
