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.
The authors would like to thank D. Passingham and H. Lau for valuable comments and T. Mildner and S. Zysset for help with scanning. This work was funded by the Max Planck Society and the German Federal Ministry of Education and Research.
Supplementary Figures 1–9, Table 1, Methods and Discussion