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Conscious Intention and Motor Cognition. Patrick Haggard, Trends in Cognitive Sciences Vol. 9, No. 6, pp. 290~295 ,2005. 2010.08.04 Seung-hyun Lee Soft Computing Lab. Contents. Introduction Thought on intention: Past vs Present Libet’s experiment Action Generation Selection
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Conscious Intention and Motor Cognition Patrick Haggard, Trends in Cognitive Sciences Vol. 9, No. 6, pp. 290~295 ,2005 2010.08.04 Seung-hyun Lee Soft Computing Lab.
Contents • Introduction • Thought on intention: Past vs Present • Libet’s experiment • Action • Generation • Selection • Urge & effect • Linking urge to effect • Conclusion
Introduction Q) What is left over if I subtract the fact that my arm goes up from the fact that I raise my arm?’ A)Intention to move one’s arm - prior intention - intention in action
Past Thoughts on intention • A computational framework for action
Past Thoughts on intention(cont’d) • Prevalent idea for action: Decartes
Present Thoughts on intention(cont’d) • Conscious experiences = consequences of brain activity • Why? • No direct nor strong tools for studying intention • Evasive conscious experience of intending : lack of vivid quality of visual phenomena • Changes in dominant view : action as conditioned responses to environmental stimuli
Libet’s Experiment • Setup
Libet’s Experiment(Cont’d) • Result Conscious intention is not the cause of action
Libet’s Experiment(Cont’d) • Possibilities • Conscious intention could be part of an illusion of mental causation, retrospectively inferred to explain behavior • Conscious intention could be an immediate consequence of the brain processes which prepare action
Libet’s Experiment(Cont’d) • Supporting experiments • Lau et al. • Used fMRI • Judging action vs judging intention • Greater activation on pre-supplementary motor area & intra-parietal sulcus for judging intentions • Sirigu et al. • Patients with focal cerebellar or parietal lesions • Parietal group showed delay in the awareness of conscious intention
Action Generation • Features • Goal-directed. Intention through to the intended effect == Ideomotor • Involving a pervasive process of information expansion • Two aspects of will • Internal generation • Ex) reflexes • Selection or choice between alternative possible actions
Action Selection ? • Haggard and Eimer’ s study • Two subject groups: showing early and late judgement of intention • Readiness potential W judgement (X) • Lateralised readiness potential W judgement (O) Conscious intention is linked to the specific preparation to perform a particular movements
Action Selection(cont’d) ? • Studies • Ammon & Gandevia : Transcranial Magnetic Stimulation(TMS) no awareness of altered responding • Brasil-Neto et al. • : TMS go signal later responses were unaffected
Urge & Agency Conscious Intention
Urge Conscious Intention(Cont’d) • Fried et al.’s experiment • Stimulations of the cerebral cortex via electronodes • Result • Feeling of an urge to move a specific body part during the low intensity stimulation • Real movement under higher stimulation conscious intentions are at least partly preconstructions rather than reconstructions
Sense of Agency Conscious Intention(Cont’d) • Reflexive feeling that ‘I’ control events in the outside world • Agency as an illusion of mental causation • Post-hoc reconstruction of agency • People can incorrectly infer agency based on repeated associations between events which are in fact unrelated • An experiment by Wegner and Weatley Experience that I cause the event
Sense of Agency Conscious Intention(Cont’d) • Anarchic Hand Syndrome(AHS) by Marcel • Patients with frontal lobe and callosal damage • Perform well-formed actions in response to environmental cues • But actions are contrary to the patient’s will, and occur without preceding conscious intention • Della Sala et al’s supporting example • Two sources of actions • Ownership of action - agency • Ownership of the source of action - urge
Linking Urge to Agency Conscious Intention(Cont’d) • Haggard et al. • Experiment: Indicate time of action and effect • Result
Conclusion • It seems extremely HARD to apply in agent system • Studies on imitation • People typically imitate other’s goal • Not the movements they use to achieve them • Bekkering, H. et al., “Imitation of gestures in children is goal directed,” Q. J. Exp. Psychol. A 53, 153–164, 2000 • Additional reference(decision making) • A. Dijksterhuis, et al., “On Making the Right Choice: The Deliberation-Without-Attention Effect,” Science, vol. 311, no. 5763, pp. 1005-100