The search for invertebrate consciousness.

Summary

There is no consensus on whether invertebrates are conscious or how to test for it. Theory-heavy and theory-neutral approaches have serious problems, so a middle path called the theory-light approach is proposed. It relies on a minimal commitment: conscious perception facilitates a cluster of cognitive abilities relative to unconscious perception. This facilitation hypothesis can guide a systematic search for consciousness-linked cognitive abilities in invertebrates, focusing on their relationships and sensitivity to masking, rather than more theory or undirected data gathering.

Study at a glance

Abstract

There is no agreement on whether any invertebrates are conscious and no agreement on a methodology that could settle the issue. How can the debate move forward? I distinguish three broad types of approach: theory-heavy, theory-neutral and theory-light. Theory-heavy and theory-neutral approaches face serious problems, motivating a middle path: the theory-light approach. At the core of the theory-light approach is a minimal commitment about the relation between phenomenal consciousness and cognition that is compatible with many specific theories of consciousness: the hypothesis that phenomenally conscious perception of a stimulus facilitates, relative to unconscious perception, a cluster of cognitive abilities in relation to that stimulus. This "facilitation hypothesis" can productively guide inquiry into invertebrate consciousness. What is needed? At this stage, not more theory, and not more undirected data gathering. What is needed is a systematic search for consciousness-linked cognitive abilities, their relationships to each other, and their sensitivity to masking.