Consciousness as a graded and an all-or-none phenomenon: A conceptual analysis.

The issue whether consciousness is a graded or an all-or-none phenomenon has been and continues to be a debate. Both contradictory accounts are supported by solid evidence. Starting from a level of processing framework allowing for states of partial awareness, here we further elaborate our view that visual experience, as it is most often investigated in the literature, is both graded and all-or-none. Low-level visual experience is graded, whereas high-level visual experience is all-or-none. We then present a conceptual analysis starting from the notion that consciousness is a general concept. We specify a number of different subconcepts present in the literature on consciousness, and outline how each of them may be seen as either graded, all-or-none, or both. We argue that such specifications are necessary to lead to a detailed and integrated understanding of how consciousness should be conceived of as graded and all-or-none.