Subjectivity "Demystified": Neurobiology, Evolution, and the Explanatory Gap.

Todd E Feinberg,Jon Mallatt

doi:10.3389/fpsyg.2019.01686

Abstract

While life in general can be explained by the mechanisms of physics, chemistry, and biology, to many scientists and philosophers, it appears that when it comes to explaining consciousness, there is what the philosopher Joseph Levine called an “explanatory gap” between the physical brain and subjective experiences. Here, we deduce the living and neural features behind primary consciousness within a naturalistic biological framework, identify which animal taxa have these features (the vertebrates, arthropods, and cephalopod molluscs), then reconstruct when consciousness first evolved and consider its adaptive value. We theorize that consciousness is based on all the complex system features of life, plus even more complex features of elaborate brains. We argue that the main reason why the explanatory gap between the brain and experience has been so refractory to scientific explanation is that it arises from both life and from varied and diverse brains and brain regions, so bridging the gap requires a complex, multifactorial account that includes the great diversity of consciousness, its personal nature that stems from embodied life, and the special neural features that make consciousness unique in nature.

Highlights

The multifactorial basis of conscious experience, including its foundations in life processes, its widespread neural organization, its diversity both within and across species, and its uniqueness in biology and all of nature, make it exceedingly difficult if not impossible to encapsulate or “pinpoint” its biological and neurobiological substrate and cause in the way, for instance, that photosynthesis can account for energy creation in plants or that DNA can account for the mechanisms of hereditary
Despite the phenomenal and neurobiological diversity, we propose that the subjective, phenomenal, aspects of experience can be explained using the principles of normal physics, chemistry, and biology
We have built the case that there are no scientific “gaps” in the neurobiology and evolution of consciousness, but rather a seamless series of transitions between levels of increasing neural differentiation, complexity, and hierarchy that lead to phenomenal consciousness

Summary

INTRODUCTION

The features include an explosion of special senses (image-forming eyes, acute hearing, and keen smell) and of neuron types; many new neural processing subsystems; more integration of information from the different senses; more hierarchic levels of neurons for processing information; extreme reciprocal and oscillatory crosscommunication between the lower and higher levels and between participating brain regions (Lamme, 2006; Koch et al, 2016; Northoff, 2016; Nunez, 2016; Grossberg, 2017); more effective attention; and more memory From these features arise the extraordinary neurobiological system-properties of complex brains in a way comparable to how life naturally arises from the interactions of its subcellular and cellular components.

In different animal groups

DISCUSSION