Fundamentally Stochastic

I have just finished reading a 2005 paper from Games and Economic Behavior entitled "Physiological utility theory and the neuroecomics of choice" by Glimcher et al. This is the best paper on neuroeconomics that I have read and follows along almost exactly the same lines that I have been pondering for my doctoral research. A thought came to my head while reading the paper that I found quite interesting.

Much data is presented in the paper that suggests that the precise pattern of activity in cortical neurons is stochastic. "The dynamics of exactly when an action potential is generated seems to depend on truly random physical processes." I have discovered this point of view previously in Dayan and Abbott's Theoretical Neuroscience, where they model action potentials using essentially Poisson processes. The fact that struck me is related to one of the common sticking points of the analysis of game theory: mixed stratgey equilibrium. The (very basic) idea is that actions in a game are in a stable equilibrium if the players of the game impose a probabilistic structure to their choice behavior. The problem that I often find when talking to people about this is that it does not matter if equilibrium exists if each of two actions is chosen 50% of the time, how does one actually do that outside of flipping a coin. Furthermore, in one-shot games, this concept of equilibrium seems to be lacking in that one intuitive thinks that a nonrandom choice would be better than simply rolling a die. The interesting idea that I garned from this paper is that the stochastic nature of a mixed strategy equilibrium is actually naturally encoded in our actions by the fundamental stochasticity of synaptic transmission.

I am essentially saying that stochastic analysis of game theory is not only elegant in that it provides equilbirum conditions under very general settings as described by Nash, but further it is essential to the understanding of real human behavior. The physiology of decision making is stochastic in nature. This in itself is enough to reject Descartes' dualism. This paper explicates this rejection along with the rejection of the point of view held by many current economists that decision making is divded into two parts: a rational component controlled by the cerebral cortex and an irrational component controlled by a separate part of the brain more associted with emotions. I believe I have even stated this point of view in a previous post. However, this was from my point of view as an amateur in the field of neuroscience.

The current view of the biology field seems to hold that decision making is made by the brain in a more unitary approach and that rational and irrational outcomes come from the same process. Henceforth, a predictive model must be able to unify both rational and irrational choices behavior and have the means of determining when each will occur. It is this goal that I think will be most fruitful going forward and which I intend to pursue.