Unconscious determinants of free decisions in the human brain

Abstract

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.

Influences of unconscious priming on voluntary actions: Role of the rostral cingulate zone

“…4 Soon, Brass, Heinze, & Haynes, 2008;Soon, He, Bode, & Haynes, 2013). Intuitively one would think that free choices are mostly determined by our own intentions and internal goals.…”

Brain circuits implicated in psychogenic paralysis in conversion disorders and hypnosis

“…This region is also activated in response to incidental information related to the self without explicit task demands or conscious will [58]. On the other hand, the precuneus is more particularly recruited during autobiographical memory retrieval tasks involving self-centered perspective and sensory imagery [14], as well as judgment of self-agency in actions [27] or free motor choices [87]. Finally, more lateral regions of right ventral prefrontal cortex have been linked with motor inhibition processes promoted by threat signals [79], consistent with a more general role in inhibitory control and avoidance in negative emotional contexts [32,40,41].…”

Distinct dynamical patterns that distinguish willed and forced actions

“…Another possible interpretation of these findings is that the number of cells in frontal areas in which these differences are realized may be few and insufficient to produce a measurable field. Furthermore, as reported by (Soon et al 2008) in an fMRI study, there was no increase in signal strength in frontal regions during a decision but rather, predictive information was encoded in differences in spatial patterns of fMRI measurements, and so the methods discussed in this study may be best suited for detecting differences in signal strength rather than fine spatial changes in neural activity.…”

“…Neuroimaging evidence suggests that motor behaviour is initiated in frontal cortices and that the sense of volition occurs after a corollary discharge in multiple brain areas (Hallett 2007), and points to a close relation between the activity in frontal and parietal cortices which can precede the outcome of a free decision by up to 10 s (Soon et al 2008). We did not find much contribution from frontal areas, which may be attributed to the almost ''mechanical'' task considered here, where symbols are designed to be very intuitive so that they can be directly interpreted without a large cognitive load.…”

“…This suggests that some part of an individual's brain already ''knows'' about the execution of a motor act before that information is consciously accessible and this observation has motivated increased interest in the study of free will and its physiological basis. Recent primate studies have suggested that the interaction between frontal and parietal cortices is fundamental for free choice and decision making (Pesaran et al 2008;Soon et al 2008). Parietal cortex has been implicated in movement intention and awareness (Desmurget and Sirigu 2009), and frontal cortices have been thought to play an important role in decision making and willful acts (Frith et al 1991;Ingvar 1994;Manes et al 2002;Pesaran et al 2008;Rushworth 2008).…”