Original Research ARTICLE
Free will emerges from a multistage process of Target assignment and Body-scheme recruitment for Free effector selection.
- 1University Medical Center Groningen, Netherlands
Self-intended action implies an initial stage of assigning an external entity as target of action, with subsequent recruitment of body-scheme information serving the free selection of an appropriate effector system to achieve the action aim. This plurality underscores the concept that neuronal response freedom underlying the generation of such action is not necessarily restricted to a singular cerebral event at its initiation, but that such freedom is embedded in a series of successive processing steps. In this respect, action intention initially concerns the transition of a neutral object into a target of action, while the 'will' to act further crystalizes with the recruitment of one's body scheme. The latter is a prerequisite for effector selection and indeed complements the emerging sense of agency. This temporal order of neuronal events fits a model of fronto-parietal interactions associated with volition.
A concise behavioural experiment is additionally described, in which successively displayed balls represent either a recognisable object with distinct shape and colour features, or a target of action. Instructions to write down the ball’s characteristics were alternated by the command 'action'. When shifting from a neutral object to an action target, the ball was placed in one of three backgrounds: empty, an outdoor goal or indoor basket. In response to the action command, subjects reported intended actions such as kicking, seizing, throwing and heading, thus implicitly referring to the foot, hand or head as chosen effector. For the latter the parietal cortex is strongly implicated, not only concerning predefined but also free selection. Although subjects were free to choose what to do with the ball, the environmental cues of the ball strongly influenced their choices.
These results illustrate the temporal order in fronto-parietal processing associated with initial target assignment, instantly followed by the embodiment of will, i.e. the recruitment of body-scheme information for possible effector selection. Such multistage neuronal processing underlying free action selection underscores that the onset of brain signals prior to the perceived sense of free will is not a valid argument to reduce free will to an illusion.
Keywords: Embodiment of will, body scheme, free effector selection, parietal cortex, Volition
Received: 30 Aug 2018;
Accepted: 07 Feb 2019.
Edited by:Sebo Uithol, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Netherlands
Reviewed by:Ricardo De Oliveira-Souza, Instituto D'Or de Pesquisa e Ensino (IDOR), Brazil
Alfred Mele, Florida State University, United States
Copyright: © 2019 De Jong. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Bauke M. De Jong, University Medical Center Groningen, Groningen, Netherlands, firstname.lastname@example.org