Francis Crick on freewill
Francis Crick. 1994. A Postscript on Freewill. In The Astonishing Hypothesis: The Scientific Search for the Soul. Scribner Book Company. HKU intranet
M.F.S. Rushworth , M.E. Walton , S.W. Kennerley and D.M. Bannerman. 2004. Action sets and decisions in the medial frontal cortex. Trends in Cognitive Sciences, 8:9. doi:10.1016/j.tics.2004.07.009
Frédéric Assal, Sophie Schwartz, Patrik Vuilleumier (2007) "Moving With or Without Will: Functional Neural Correlates of Alien Hand Syndrome," Annals of Neurology doi:10.1002/ana.21173
Architecture: computation → many action plans → the chosen plan → action
We have conscious access to the action plans and the plan that is decided, but not the computations involved in producing the list of plans or in selecting the decided plan.
We think we have freewill because the decision is unpredictable (perhaps because of chaos).
We might be able to infer the reasons that go into the computations for the decisions, but we might also confabulate.
Freewill is located at the brain region known as anterior cingulate sulcus. Arguments:
This area is damaged in the woman who has "lost her will", with "nothing to say."
This area receives inputs from higher sensory systems and is located at the higher levels of the motor system. It is connected to the corpus striatum on both sides of the brain.
This part is also damaged in a patient with the alien hand syndrome (together with damage in the corpus callosum.)
June 4, 2004 American Journal of Psychiatry
@The study identified lower brain activity in the anterior cingulate gyrus of compulsive hoarders, compared with other OCD patients.@
Rushworth et. el. (2004) ACC encodes reinforcement value of action outcomes.
The Alien hand syndrome
@For instance, his left hand could grasp and manipulate parts of clothes or objects, even tear them into pieces, while the patient was seating in his armchair and unaware of these involuntary movements.@
VIDEO Video: http://www.youtube.com/v/H0uaNn_cl14
Multiple unconscious decision plans.
Competitive network selects final decision.
Selection moderated by attention.
Winner-take-all competitive network. White: inhibitory; Black: excitory
See recent research by Assal et. el. (2007).