Getting technical about awareness.

It has recently been argued that post-decision wagering provides an objective measure of awareness. We critically evaluate this claim, emphasizing the distinction between performance without awareness and a reluctance to gamble in full awareness of weak sensory evidence. We address two key methodological issues. The first is the design of the pay-off matrix to reward a strategy of wagering that reflects the strength of sensory evidence. The second is the use of signal detection theory to analyze the resulting data. We argue that proper treatment of these issues is essential if post-decision wagering is to prove valuable in validating claims of perception without awareness in normal subjects and neuropsychological patients.