Presentation is loading. Please wait.

Presentation is loading. Please wait.

The Neural Bases of Cognitive Conflict and Control in Moral Judgment Joshua D. Greene, Leigh E. Nystrom Andrew D. Engell,John M. Darley, and Jonathan D.

Similar presentations


Presentation on theme: "The Neural Bases of Cognitive Conflict and Control in Moral Judgment Joshua D. Greene, Leigh E. Nystrom Andrew D. Engell,John M. Darley, and Jonathan D."— Presentation transcript:

1 The Neural Bases of Cognitive Conflict and Control in Moral Judgment Joshua D. Greene, Leigh E. Nystrom Andrew D. Engell,John M. Darley, and Jonathan D. Cohen Neuron, Vol. 44, 389–400, October 14, 2004

2 What is the distinction between personal and impersonal moral dilemmas? What governs the decision in each case? What is utilitarian decision?

3 Distinction between impersonal and personal E.g. trolley vs. footbridge Evolution of morality? Animal has personal because they have emotions We add impersonal because we have extra reasoning capacity Looking for evidence that personal are driven by socio- emotional decisions and that impersonal more cognitive What is the evidence already?

4 Previous work: 1) Brain areas associated with socio-emotional increased activity during personal 2) Brain areas associated with abstract reasoning and problem solving increased activity during impersonal 3) Reaction time longer when judging personal violations as appropriate Compared with judgments inappropriate (stroop argument) Effect not seen for impersonal judgments

5 Hypotheses:

6

7

8 Translation… Longer reaction more conflicted decision ACC associated with conflict so expect more activity for trials with greater RT DLPFC involved in abstract reasoning so expect more activity for longer RT Different patterns of activity reflect differences in decision making behavior

9 To test this:

10

11 Difficult vs. easy Cognitive- emotional conflict : can save the village by killing the baby vs should teenage mother kill her baby? No significant cognitive conflict

12 Figure 1. Relationships among Three Analyses The present results are from three increasingly focused analyses of a single data set drawn from 41 participants who responded to moral dilemmas while having their brains scanned using fMRI.

13 Methods How much do we assume that people know? What are the necessary details? What kind of things can we leave out? Can we give examples…?

14 41 participants (24M 17F) Right handed 3 ditched for technical reasons Stimuli http://www.neuron.org/cgi/content/full/44/2/389/DC1 Presentation: 12 blocks 5 trials Dilemma presented as text on 3 screens 2 for scenario and last for choice Button press – appropriate or not 14 secs between trials RT normalized to individual personal time

15

16 Figure 2. Difficult versus Easy Personal Moral Judgment Selected brain regions (see Table 2) exhibiting significantly increased activity for difficult (high-RT), as compared to easy (low-RT), personal moral judgment: anterior cingulate cortex (BA 32), posterior cingulate cortex (BA 23/31), precuneus (BA 7), right and left middle frontal gyrus (BA 10/46). Statistical maps of voxelwise t scores were thresholded for significance (p 0.0005) and cluster size (8 voxels). (A) Sagittal slice plane is x 0; (B) axial slice plane is z9 (Talairach and Tournoux, 1988). Image is reversed right to left according to radiologic convention.

17

18 Figure 3. Utilitarian versus Nonutilitarian Difficult Personal Moral Judgment Selected brain regions (see Tables 3–4) exhibiting significantly increased activity for utilitarian, as compared to nonutilitarian, difficult personal moral judgment. (A) A spatially restricted analysis (p 0.05, cluster size 8) of activity in the anterior dorsolateral prefrontal cortex (BA 10/ 46) revealed bilateral clusters of voxels exhibiting increased activity during trials in which participants made utilitarian judgments. 1988). (B) A whole-brain analysis (p 0.005, cluster size 8) revealed a contiguous and slightly anterior region on the right side exhibiting the same effect. (C) Time course of activity in this region by participant response: utilitarian/“appropriate” (green) versusnonutilitarian/“inappropriate” (red). Data are not adjusted for hemodynamic lag.

19

20

21 Predicted that difficult personal moral dilemmas would exhibit increased ACC activity What is the role of the ACC? Conflict monitoring Error detection Attention to action (regulative) Cardiovascular arousal Predicted increase in anterior DLPFC activity What is the role of the DLPFC?

22 How to describe imaging data and large tables…. What are the key points? How much detail should we skip?

23 Conflict and control ACC and DLPFC both increase for difficult decisions Does ACC recruit DLPFC after noticing difficulty? Or does activation of DLPFC allow greater competition with emotional input?

24 Cognition and emotion Cognitive process (Kohlberg) Emotion first and then rationality follows after the fact in response to social demands (Haidt) Both emotion and cognition have roles in moral judgment (Greene and Haidt) Can be complementary or competitive

25 Relationship between cognition and emotion Posterior cingulate (emotive area) also involved in utilitarian decision - ie not purely cognitive Suggest that ACC acts to motivate to engage in the necessary reasoning. BA23/31 (posterior cingulate) motivates to respond in accordance with judgment Is the distinction between cognition and emotion real?

26 Finally a resolution to John Stuart Mill and Immanual Kant…

27 Damage to the prefrontal cortex increases utilitarian moral judgements Michael Koenigs, Liane Young, Ralph Adolphs, Daniel Tranel, Fiery Cushman, Marc Hauser & Antonio Damasio Nature 446 2007 908-911

28 6 patients with bilateral damage to VMPC – ventromedial prefrontal cortex A region associated with normal generation of emotions esp social emotions 12 brain damaged (not emotional areas ie VMPC, amygdala, insula..) 12 normals – no brain damage Stimuli presented as text on 3 screens answered yes I would or no I would not by button Scenarios – non moral, personal (low or hi conflict), impersonal

29 Figure 1 | Lesion overlap of VMPC patients. Lesions of the six VMPC patients displayed in mesial views and coronal slices. The colour bar indicates the number of overlapping lesions at each voxel.

30 Figure 2 | Moral judgements for each scenario type. Proportions of ‘yes’ judgements are shown for each subject group. Error bars indicate 95% confidence intervals. We used three classes of stimuli: non-moral scenarios (n518), impersonal moral scenarios (n511), and personal moral scenarios (n521). On personal moral scenarios, the frequency of endorsing ‘yes’ responses was significantly greater in the VMPC group than in either comparison group (P values,0.05, corrected).

31 Figure 3 | Moral judgements on individual personal moral scenarios. Proportions of ‘yes’ judgements given by each subject group for each of the 21 personal moral scenarios. Individual scenarios (numbered 1–21 on the x axis) are ordered by increasing proportion of ‘yes’ responses given by the normal comparison group. Responses did not differ between subject groups for the low-conflict scenarios (left of the vertical line). The VMPC group made a greater proportion of ‘yes’ judgements than either comparison group for every one of the high-conflict scenarios (right of the vertical line).

32 Ventromedial Pre-frontal cortex involved in utilitarian judgments -Suggest VMPF necessary for normal judgment, ie need to include emotion in decision -So emotion not just a consequence of the decision Knowledge of social and moral norms same for both ( acquired pre-damage) No longer have access to social emotions

33 How to resolve discrepancies between papers…. The two papers mostly agree but not completely… Do we gloss over this and keep moving? Do we focus on it and try to explain it? Any other strategy?


Download ppt "The Neural Bases of Cognitive Conflict and Control in Moral Judgment Joshua D. Greene, Leigh E. Nystrom Andrew D. Engell,John M. Darley, and Jonathan D."

Similar presentations


Ads by Google