Could we perceive the world differently than we do? Neuroscience-based emergentism and the biological function of consciousness

Abstract

Whether consciousness serves a biological and psychological function is a topic of intense interest. We reexamine this issue by first focussing on an objection against consciousness having a function raised amongst others by Jaegwon Kim. His argument targets a form of non-reductive physicalism stating that consciousness has causative power beyond that of the physical substrate. In contrast, we argue for a monistic conceptualization in which high-level, phenomenal representations correspond to low-level, neuronal representations, together constituting one functional entity. This neurorepresentationalist position supports a non-classical emergentism in which phenomenal consciousness and its neural substrate cannot be functionally separated. We next ask why our perceptual phenomenology is structured the way it is, making the case that conscious experiences are not accidental constructs, but are generated as a multimodal, situational survey of the brain's environment (including the body) whose features precisely function to enable deliberate, planned behaviors. This function is illustrated by, for instance, examining why we see the world 'upside up' instead of 'upside down', why multisensory integration and other forms of integration are biologically useful, and what function spatial object constancy has in the face of ongoing eye and body movements. Pathological cases of hallucination, such as Anton and Bonnet syndrome, further buttress the argument by showing how behavior can be severely impaired when conscious brain systems misrepresent reality. Finally, we compare neurorepresentationalism to other proposals on functions of consciousness, and especially point out some differences with proposals for a learning function of consciousness.