CENTER FOR RESEARCH IN
COGNITION & NEUROSCIENCES/ConnexConnex

Since Block's seminal article in 1995, phenomenal consciousness and access consciousness are regarded by many as two types of perceptual consciousness, reflecting the qualitative nature of subjective experience and it being available for cognitive processes, respectively. Although this was a conceptual distinction aimed at clarifying the vocabulary used in the field, its adoption by the neuroscientific community has led to confusion concerning the theories and neural correlates of perceptual consciousness. As suggested by others before, rather than two types of consciousness, phenomenal aspects and access may better be conceived as two necessary conditions for perceptual consciousness. In this view, a percept is considered conscious if and only if its content is (a) encoded with an appropriate, phenomenal format, and (b) it is accessed. I will describe the implications of this shift in perspective and its power to reunite the so-called perceptual and cognitive theories of consciousness and their neural implementations. Moreover, I will present a leaky evidence accumulation model describing how those two conditions for consciousness are met in time, shedding light on three distinct thresholds between unconscious perception, conscious access, and conscious report. Finally, I will illustrate how the model can account for temporal aspects of conscious perception that are often neglected, including its subjective duration.