I am a psychologist and a materialist — I believe that all psychological phenomena have a physical basis without being reducible to it. But for the time being our psychological understanding of consciousness is incomplete — we do not yet know what it is for which we seek the physiological basis. It is not until we have a solid and preferably consensual understanding of consciousness that a neuropsychology of it will be timely, consistent, and will command general agreement.

Mandler, George. Consciousness Recovered. Psychological functions and origins of conscious thought..
Philadelphia, PA, USA: John Benjamins Publishing Company, 2002. p x.