conscious intention and motor cognition 2010.08.04 seung-hyun lee soft computing lab. patrick...

Conscious Intention and Motor Cognition

2010.08.04

Seung-hyun Lee

Soft Computing Lab.

Patrick Haggard, Trends in Cognitive SciencesVol. 9, No. 6, pp. 290~295 ,2005

S FT COMPUTING @ YONSEI UNIV . KOREA16

Contents

• Introduction

• Thought on intention: Past vs Present

• Libet’s experiment

• Action– Generation– Selection– Urge & effect– Linking urge to effect

• Conclusion

2


Introduction

3

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


Thoughts on intention

• A computational framework for action

4

Past


Thoughts on intention(cont’d)

• Prevalent idea for action: Decartes

5

Mind Ac-tion Body

Past


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

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Present


Libet’s Experiment

• Setup

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Libet’s Experiment(Cont’d)

• Result

8

Conscious intention is not the cause of action



• Possibilities– Conscious intention could be part of an illusion of mental causa-

tion, retrospectively inferred to explain behavior

– Conscious intention could be an immediate consequence of the brain processes which prepare action

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• Supporting experiments –Lau et al.

• Used fMRI• Judging action vs judging intention• Greater activation on pre-supplementary motor area & intra-parietal sulcus for judging in-

tentions

–Sirigu et al.• Patients with focal cerebellar or parietal lesions• Parietal group showed delay in the awareness of conscious intention

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Preparatory activity in the motor areas

Action Conscious in-tention


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

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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

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Selection process

Motor command

Conscious intention ?


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

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Selec-tion

process

Unconscious process ?


Conscious Intention

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Urge Effect(Agency)

Definition being about to moveprediction of the goal state

Neuron motoric sensory

Focus internal external

Correspond-ing theory

Libet's W judgementJame's ideomotor theory of action

Urge & Agency


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

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Urge



• 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 as-

sociations between events which are in fact unrelated–An experiment by Wegner and Weatley

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Sense of Agency

Conscious thought Thought-about

event

ActionExperience that I cause the event



• 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 preced-

ing conscious intention

–Della Sala et al’s supporting example

• Two sources of actions–Ownership of action - agency–Ownership of the source of action - urge

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Sense of Agency



• Haggard et al.–Experiment: Indicate time of action and effect–Result

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Linking Urge to Agency


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-At-

tention Effect,” Science, vol. 311, no. 5763, pp. 1005-100

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Thank you

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