Modified from Proceedings of the Australian Society for Biophysics, 3 ( 1979) 15-20: An invited lecture to the 3rd Annual Meeting of the Society, held at the Flinders University of South Australia, on 31 August - 2 September 1978.
Department of Human Physiology and Pharmacology, University of Adelaide
Physics has a relatively well organised conceptual basis; neurophysiology is not so advanced in this way, but has a large body of observations.
It is the purpose of this paper to explore some relationships between the ideas of physics and those of neurophysiology. The plan is to state some general principles of neurophysiology in an abstract way, so as to display their similarity to ideas used in physics to study critical phenomena.
We may compare an integrative nervous system with a physical system near a critical point. Critical states are in fluctuation dominated regimes, and are characterised by long range correlations. The integrative action of the nervous system depends upon cooperative activity of neurones, described by long range correlations between nerve cells throughout the brain and spinal cord. Besides the long range of the correlations, there is a richness of variety of correlation patterns. The need to consider high order correlation patterns is also felt in the study of physical systems far from equilibrium.