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MEG 를 이용한 고등의사결정과정의 시공간적 동역학 연구
  Spatiotemporal dynamics of high-level cognitive
          decision making: an MEG study




                   Do economists need brains?
                   The Economist Jul 24th 2008   1
2
Decision making is a very complex and fast process




                                         Decision making is processed on a
                                         millisecond temporal scale in brain
                                         networks.




      http://rulebooktothegamesoflife.
      wordpress.com/2008/08/25/rps/
MEG provides better temporal and spatial resolution




   Better temporal resolution
   fMRI
   (1~2 sec) < MEG / EEG
               (~1 msec)

                  Better spatial resolution
                  MEG / fMRI
                  (~1 mm)       >  EEG
                                   (~1 cm)


                                                  4
MEG analysis process




                                                    DLPFC

                                                    STG


                                                  PC




Data recording   Time-frequency analysis   Effective connectivity
                 Source reconstruction     analysis


                                                             5
Major novel findings
   Four steps of the decision-making process
                   in the brain

1. Awareness of information
 - the γ frequency ranges during the 50 to 100 ms
 - OFC (social & emotional)

2. Evaluation of alternatives
   - the β and γ frequency ranges during the −600 to −500 ms
   - DLPFC (rational), OFC, STG, IPL (theory of mind)

3. Decision making
   - the γ frequency range −200~−100 ms
   - DLPFC, OFC, IPL, Precuneus (fronto-parietal network)

4. Post-decision evaluation
   - the β and γ frequency range 350~500 ms
   - STG, MTG, ITG, IPL (mentalizing)

                                                               6
An apt tool to investigate complex decision-making
processes in a laboratory setting: the Ultimatum Game



           proposer                                     responder




   1. Make an offer: 9:1                 2. Conflict btwn emotion & cognition
   (send emotional cue)                  (ACC, Ins, dlPFC, vmPFC)
   Reward anticipation (NAcc)
   Optimal offer? (ToM)
                                         3. Make a decision
   4. Post-decision
   evaluation

 Game theory: the proposer should offer the smallest amount possible and
 the responder should accept any amount offered.
 Behavior: Their decision making is dependent on their personal valuation of
 fairness.                                                                   7
1. Information awareness




Inferior frontal gyrus for emotionally aware information.



                                                            8
PDC - high beta and gamma frequency band (35~50Hz)




        Response to
   A    Unfair offer
                       -800 ~ -600 ms   -600 ~ -400 ms   -400 ~ -200 ms   -200 ~ -000 ms



            OFC


               STG     -800 ~ -200 ms   -200 ~ -400 ms   -400 ~ -600 ms   -600 ~ -800 ms


                       Unfair offer is more cognitively demanding to process

            PC


        Response to
   B    Fair offer
                       -800 ~ -600 ms   -600 ~ -400 ms   -400 ~ -200 ms   -200 ~ -000 ms




         P < 0.05
         P < 0.001     -800 ~ -200 ms   -200 ~ -400 ms   -400 ~ -600 ms   -600 ~ -800 ms

                                                                                           9
                       Decreased information transmission
2. Evaluation of alternatives
   - the β and γ frequency ranges during the −600 to −500 ms
   - DLPFC (rational), OFC (social & emotional), STG, IPL (theory of mind)
3. Decision making
   - the γ frequency range −200~−100 ms
   - DLPFC, OFC, IPL, Precuneus (fronto-parietal network)
4. Post-decision evaluation
   - the β and γ frequency range 350~500 ms
   - STG, MTG, ITG, IPL (mentalizing)
                                                                             10
PDC - high beta and gamma frequency band (20~50Hz)




 A    Acceptance     -800 ~ -600 ms   -600 ~ -400 ms   -400 ~ -200 ms   -200 ~ -000 ms



            DLPFC


            STG      -800 ~ -200 ms   -200 ~ -400 ms   -400 ~ -600 ms   -600 ~ -800 ms




           PC


 B    Rejection      -800 ~ -600 ms   -600 ~ -400 ms   -400 ~ -200 ms   -200 ~ -000 ms




       P < 0.05
       P < 0.001     -800 ~ -200 ms   -200 ~ -400 ms   -400 ~ -600 ms   -600 ~ -800 ms
                                                                                         11
Right DLPFC successfully regulate other regions of the brain in acceptance.
Neurobiological insights from
   Information transfer (effective connectivity)
          between regions in the brain
• Information is processed as discrete sequential
  functional microstates.
• It is not assumed that one single neural
  population was active during a certain
  microstate.
• Many different areas can work in parallel, but
  together they form a certain spatial and
  temporal configuration.
• MEG spatiotemporal dynamics alone also cannot
  provide the large-scale network information that
  comes from oscillatory interactions between
  spatially distant cortical populations.
                                                   12
Emotion vs. Cognition




       Do economists need brains?
       The Economist Jul 24th 2008




                                     13

More Related Content

Spatiotemporal dynamics of high-level cognitive decision making: an MEG study

  • 1. MEG 를 이용한 고등의사결정과정의 시공간적 동역학 연구 Spatiotemporal dynamics of high-level cognitive decision making: an MEG study Do economists need brains? The Economist Jul 24th 2008 1
  • 2. 2
  • 3. Decision making is a very complex and fast process Decision making is processed on a millisecond temporal scale in brain networks. http://rulebooktothegamesoflife. wordpress.com/2008/08/25/rps/
  • 4. MEG provides better temporal and spatial resolution Better temporal resolution fMRI (1~2 sec) < MEG / EEG (~1 msec) Better spatial resolution MEG / fMRI (~1 mm) > EEG (~1 cm) 4
  • 5. MEG analysis process DLPFC STG PC Data recording Time-frequency analysis Effective connectivity Source reconstruction analysis 5
  • 6. Major novel findings Four steps of the decision-making process in the brain 1. Awareness of information - the γ frequency ranges during the 50 to 100 ms - OFC (social & emotional) 2. Evaluation of alternatives - the β and γ frequency ranges during the −600 to −500 ms - DLPFC (rational), OFC, STG, IPL (theory of mind) 3. Decision making - the γ frequency range −200~−100 ms - DLPFC, OFC, IPL, Precuneus (fronto-parietal network) 4. Post-decision evaluation - the β and γ frequency range 350~500 ms - STG, MTG, ITG, IPL (mentalizing) 6
  • 7. An apt tool to investigate complex decision-making processes in a laboratory setting: the Ultimatum Game proposer responder 1. Make an offer: 9:1 2. Conflict btwn emotion & cognition (send emotional cue) (ACC, Ins, dlPFC, vmPFC) Reward anticipation (NAcc) Optimal offer? (ToM) 3. Make a decision 4. Post-decision evaluation Game theory: the proposer should offer the smallest amount possible and the responder should accept any amount offered. Behavior: Their decision making is dependent on their personal valuation of fairness. 7
  • 8. 1. Information awareness Inferior frontal gyrus for emotionally aware information. 8
  • 9. PDC - high beta and gamma frequency band (35~50Hz) Response to A Unfair offer -800 ~ -600 ms -600 ~ -400 ms -400 ~ -200 ms -200 ~ -000 ms OFC STG -800 ~ -200 ms -200 ~ -400 ms -400 ~ -600 ms -600 ~ -800 ms Unfair offer is more cognitively demanding to process PC Response to B Fair offer -800 ~ -600 ms -600 ~ -400 ms -400 ~ -200 ms -200 ~ -000 ms P < 0.05 P < 0.001 -800 ~ -200 ms -200 ~ -400 ms -400 ~ -600 ms -600 ~ -800 ms 9 Decreased information transmission
  • 10. 2. Evaluation of alternatives - the β and γ frequency ranges during the −600 to −500 ms - DLPFC (rational), OFC (social & emotional), STG, IPL (theory of mind) 3. Decision making - the γ frequency range −200~−100 ms - DLPFC, OFC, IPL, Precuneus (fronto-parietal network) 4. Post-decision evaluation - the β and γ frequency range 350~500 ms - STG, MTG, ITG, IPL (mentalizing) 10
  • 11. PDC - high beta and gamma frequency band (20~50Hz) A Acceptance -800 ~ -600 ms -600 ~ -400 ms -400 ~ -200 ms -200 ~ -000 ms DLPFC STG -800 ~ -200 ms -200 ~ -400 ms -400 ~ -600 ms -600 ~ -800 ms PC B Rejection -800 ~ -600 ms -600 ~ -400 ms -400 ~ -200 ms -200 ~ -000 ms P < 0.05 P < 0.001 -800 ~ -200 ms -200 ~ -400 ms -400 ~ -600 ms -600 ~ -800 ms 11 Right DLPFC successfully regulate other regions of the brain in acceptance.
  • 12. Neurobiological insights from Information transfer (effective connectivity) between regions in the brain • Information is processed as discrete sequential functional microstates. • It is not assumed that one single neural population was active during a certain microstate. • Many different areas can work in parallel, but together they form a certain spatial and temporal configuration. • MEG spatiotemporal dynamics alone also cannot provide the large-scale network information that comes from oscillatory interactions between spatially distant cortical populations. 12
  • 13. Emotion vs. Cognition Do economists need brains? The Economist Jul 24th 2008 13