title: Brain signals do not demonstrate unconscious decision making: an interpretation based on graded conscious awareness.
abstract: Neuroscientific studies have shown that brain activity correlated with a decision to move can be observed before a person reports being consciously aware of having made that decision (e.g., Libet, Gleason, Wright, & Pearl, 1983; Soon, Brass, Heinze, & Haynes, 2008). Given that a later event (i.e., conscious awareness) cannot cause an earlier one (i.e., decision-related brain activity), such results have been interpreted as evidence that decisions are made unconsciously (e.g., Libet, 1985). We argue that this interpretation depends upon an all-or-none view of consciousness, and we offer an alternative interpretation of the early decision-related brain activity based on models in which conscious awareness of the decision to move develops gradually up to the level of a reporting criterion. Under this interpretation, the early brain activity reflects sub-criterion levels of awareness rather than complete absence of awareness and thus does not suggest that decisions are made unconsciously.
authors.affiliation: Department of Psychology, University of Otago, Dunedin, New Zealand. Electronic address: miller@psy.otago.ac.nz.
authors.forename: Jeff
authors.initials: J
authors.lastname: Miller
authors.affiliation: University of Potsdam, Department of Psychology, P.O. Box 60 15 53, D-14415 Potsdam-Golm, Germany. Electronic address: wschwarz@uni-potsdam.de.
authors.forename: Wolf
authors.initials: W
authors.lastname: Schwarz
mesh_terms: D001364:Awareness / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D003243:Consciousness / Q000502:physiology*; D003657:Decision Making / Q000502:physiology*; D006801:Humans
keywords: Consciousness; Decision making; Libet; Neuroscience