Order and chaos in neural systems: An approach to the dynamics of higher brain functions

The author distinguishes between reflexes and higher processes in the brain primarily on the basis of the time elapsed between stimulus and action. The sustained neural activity associated with higher functions is explained by the complex connectivity between the new systems of sensory and motor cortical areas, in particular the many feedback and reentrant pathways. Redundancy and cooperativity are assumed to have important functions, supplanting the pulse logic of primitive nervous systems. The modification of ongoing neural activity as due to a flow of information from the microscales to the macroscales is considered. The brain is distinguished from other macroscopic systems by the fact that its mechanisms span an enormous range of scales. Information storage is believed to be diffusely distributed in the microscale, hence virtually inaccessible to an observer. It is expressed as macroscopic neural features through processes akin to turbulence.