Nature Neuroscience
Published online: 13 April 2008 | doi:10.1038/nn.2112
Unconscious determinants of free decisions in the human brain
Chun Siong Soon1,2, Marcel Brass1,3, Hans-Jochen Heinze4 & John-Dylan Haynes1,2
There has been a long controversy as to whether subjectively 'free' decisions are determined by brain activity ahead of time. We found that the outcome of a decision can be encoded in brain activity of prefrontal and parietal cortex up to 10 s before it enters awareness. This delay presumably reflects the operation of a network of high-level control areas that begin to prepare an upcoming decision long before it enters awareness.