The human brain and consciousness: biology or computations?

Abstract

Psychologists and neurophysiologists supporting the ‘biological brain’ theory believe that the main driving forces of brain activity are not electrical impulses (spikes), but neurotransmitters, and that at least a significant part of the cognitive activity of the brain does not occur in neural networks or populations, in general - not in the space between neurons, but within individual neurons, where the neurochemical and genetic ‘devices’ interact. From these considerations, one concludes to the principle impossibility to model cognitive functions, since reliance on chemical and genetic mechanisms is perceived as their fundamental substrate dependence, while only transferable functions can be modeled. The article provides a logical and methodological analysis of this concept and, in particular, proposes a distinction between strong and weak substrate dependency. Thus, the modulating role of neurotransmitters, abstractly speaking, can be simulated using other physical mechanisms while preserving their functions. In what follows I show that the facts and data on which the above-mentoned school relies are well assimilated by competing neural network theories