Post-decision wagering objectively measures awareness

Navindra Persaud, Peter McLeod & Alan Cowey
NATURE NEUROSCIENCE VOLUME 10, NUMBER 2, FEBRUARY 2007

The lack of an accepted measure of awareness has made
claims that accurate decisions can be made without awareness
controversial. Here we introduce a new objective measure of
awareness, post-decision wagering. We show that participants
fail to maximize cash earnings by wagering high following
correct decisions in blindsight, the Iowa gambling task and
an artificial grammar task. This demonstrates, without the
uncertainties associated with the conventional subjective
measures of awareness (verbal reports and confidence ratings),
that the participants were not aware that their decisions were
correct. Post-decision wagering may be used to study the
neural correlates of consciousness.

Fulltext: http://www.nature.com/neuro/journal/v10/n2/pdf/nn1840.pdf
Also see the comment by Christof Koch: http://www.nature.com/neuro/journal/v10/n2/pdf/nn0207-140.pdf