Abstract

Consciousness involves phenomenal experience, self-awareness, feelings, choices, control of actions, a model of the world, etc. But what _is_ _it?_ Is consciousness something specific, or merely a byproduct of information processing? Whatever it is, consciousness is a multi-faceted puzzle. Despite enormous strides in behavioral and brain science, essential features of consciousness continue to elude explanation. Unresolved problems include: 1) Neural correlates of conscious perception apparently occur too late—150 to 500 milliseconds (msec) after impingement on our sense organs—to have causal efficacy in seemingly conscious perceptions and willful actions, often initiated or completed within 100 msec after sensory impingement. For example in the