Noise and Rationality
This chapter highlights the role of noise in decision-making processes, its nature, and its consequences on behaviour and rationality. Noise is a prerequisite for the system to generate a choice, and synaptic noise is considered to be the main source of noise in the nervous system. At the network level, these phenomena can be amplified by bifurcation processes, especially in networks that rely on populations of excitatory and inhibitory neurons interconnected randomly. This bifurcation phenomenon belongs to what physics calls chaotic processes. Associated with stochastic phenomena, bifurcation leads to equilibrium states that can be very far apart. This chapter then goes on to explain that the very basis of the apparent irrationality of behaviour is intrinsic to the properties of the decision-making network. This approach provides an alternative explanation to individual and inter-individual variability in behaviour. The variability of behaviour that results from these processes may provide an evolutionary advantage by allowing individuals of each species to be able to switch from exploitation to exploration behaviour.