I heard an interesting talk recently by a Stanford neuroscientist.<p>He was studying standing waves of brain activity among circularly linked groups of neurons. Neurons can provide both excitatory inputs and inhibitory inputs to other neurons.<p>For a computer programmer, it is easy to imagine excitatory and inhibitory localized phenomena giving rise to all sorts of interesting and complex self-sustaining standing waves.<p>Think of the study of cellular automata by Stephen Wolfram and others, in which various simple localized rules give rise to all sorts of interesting computational phenomena, up to and including Turing Completeness.<p>In animal models such as pigs, these standing waves can be observed to persist for months if not longer.<p>His particular area of interest is to subject the brain to gentle sub-lethal doses of radiation treatment in order to change selected standing waves.<p>My thought is that there may be a qualitative difference between the underlying "neural hardware" and the thought processes that "execute" on this hardware.<p>It is the bread and butter of computer scientists to reason in a world in which the complexity of software greatly exceeds the simple computational artifacts on which it runs.<p>One might say that chess has information content that is qualitatively dissimilar to the wood-working needed to make a pretty chess board.<p>The information content in DNA is composed of chemically interchangeable A, G, T, and C molecules. So, one might say that the underlying physics is "walled off" from the information content of the DNA. Evolution has, as it were, a free hand to encode advantageous alleles, with no bias introduced by the underlying physics or chemistry.<p>All this is to say "Hear hear!" to this excellent article.<p>The "metaphorical brain talk" the author describes may indeed be a conceptual limitation if applied too broadly to the mind.