CONSCIOUSNESS AND COMMENTARIES

There are several neuropsychological syndromes in which good residual function is retained in the absence of acknowledged awareness, among t hem blindsight, amnesia, and unilateral neglect. All of them point to the need in studying conscious awareness not only for an ''on-line'' d emonstration of the relevant capacity, but for an independent commenta ry or classificatory response by the subject, whether human or animal. The parametric limits of blindsight (visual discrimination without aw areness) can be measured using a ''commentary key'' psychophysical par adigm, and the results may possibly allow an approach to identifying n eural structures involved in visual awareness.