The Search for Neural Correlates of Consciousness

The science of consciousness begins with the search for the neural correlates of consciousness. I explain this notion and give examples of research in the field. I then discuss how different conceptions of consciousness may influence the search for the neural correlates. This includes the distinctions between access and phenomenal consciousness, and between conscious states and unified conscious fields, as well as phenomenological conceptions. Finally, I discuss what finding the neural correlates may imply for the metaphysics of consciousness, in particular for the theory that conscious states are identical to brain states. Most consciousness researchers, almost no matter what their views of the metaphysics of consciousness, can agree that the first step in a science of consciousness is the search for the neural correlate of consciousness (the NCC). The reason for this agreement is that the notion of ‘correlation’ doesn’t by itself commit one to any particular metaphysical view about the relation between (neural) matter and consciousness. For example, some might treat the correlates as causally related, while others might view the correlation as evidence for identity between conscious states and brain states. The common ground therefore seems to be that the scientific search for the NCC is largely independent of the metaphysics of consciousness. Though contributors to this debate generally set aside metaphysical issues, they do acknowledge that one’s conception of consciousness is important to the search for the NCC. One will not know what one is looking for, or how to look for it, if one’s concept of consciousness is confused or otherwise unclear. Researchers with different concepts of consciousness are likely to arrive at quite different NCCs, or to disagree about the prospects of finding an NCC. In section 1, I explain the basic idea of the NCC, together with some paradigm NCC studies in the science of consciousness. In sections 2 and 3, I review the two above issues, concerning the conception of consciousness and the metaphysics of consciousness.