Brain Asymmetry,Individual-Level and Population-Level Asymmetry as Minimization of Energy and Free Energy

Abstract

Asymmetries in the organization of the nervous system have been observed in many animals of different species, from the nematode C. elegans to humans, attracting considerable attention and stimulating studies and the formulation of hypotheses aimed at understanding the existence and behavioral consequences of brain asymmetries at both the individual and population levels. We show that these asymmetries and the various phenomenological aspects of brain asymmetry, for example, sparing of neural tissue, control of motor responses and, at the population level, evolutionarily stable strategies in mathematical game theory arise as consequence of the general principles of minimization of energy and free energy, characterizing the lowest energy state. The resulting model covers all the different aspects of current models. At the individual level, the antisymmetric configuration realizes the lowest energy state of the system. At the population level, the minimization of free energy induces the emergence of directional asymmetry and collective properties of the population. For a large number of components, the population is felt by each of them as a whole collective agent rather than as a collection of individuals.