1. Examples of pattern-recognition and fMRI applied to real-world problems: Pain also Class-recap and discussion

2. Notes on grades, submitting, etc.
If you haven’t sent in answers to all the mini-Qs yet, please do
50% of grade is for mini-Qs. Mostly present/absent
I’ll be sending out list of what you have and haven’t sent, but check your own mail archive first
Graduating seniors:
I’m meant to upload your grades first
Don’t panic or stress out about the project
If you are having difficulties, send me a mail

3. Pain Pain is good! - in small doses
People lacking pain perception break their bones, burn themselves, etc.
Chronic pain is a huge problem
Lots of suffering, lost productivity, health issues, etc.
Chronic pain syndrome:
Pain that lasts more than 3 months
E.g. injury has healed, but pain doesn’t go away
There’s no obvious target for surgery
Is it “in your head” ? Is it “in your brain” ?
Are the above two statements different?

4. Social pain
Eisenberger, Naomi I., Matthew D. Lieberman, and Kipling D. Williams. "Does rejection hurt? An fMRI study of social exclusion." Science (2003): Video:

5. Social pain and the anterior cingulate
Eisenberger, Naomi I., et a.. "Does rejection hurt? An fMRI study of social exclusion." Science (2003)

6. Social pain and physical pain
Kross, E., Berman, M. G., Mischel, W., Smith, E. E., & Wager, T. D. (2011). Social rejection shares somatosensory representations with physical pain. PNAS, 108(15),

7. Not so fast! Reverse inference
What is wrong with the following reasoning?
Pain activates the anterior cingulate cortex (ACC)
Therefore, if the ACC is active then someone is feeling pain
Iannetti, G. D., Salomons, T. V., Moayedi, M., Mouraux, A., & Davis, K. D. (2013). Beyond metaphor: contrasting mechanisms of social and physical pain. Trends in cognitive sciences, 17(8),

8. Some possible alternative explanations
Maybe the anterior cingulate cortex is involved in lots of different functions, and pain is just one of them
Maybe physical pain and social pain activate the same regions of neural tissue, but finer-scale neural patterns within that region are different

9. Neural decoding of pain
Video:
Brain/ab830bde7d3e998d26f64365ed2028be

10. Neural decoding of pain
Wager, T. D., Atlas, L. Y., Lindquist, M. A., Roy, M., Woo, C. W., & Kross, E. (2013). An fMRI-based neurologic signature of physical pain. New England Journal of Medicine, 368(15),
Key points:
Expose normal healthy subjects to thermal pain
Ask people to give behavioural ratings
Train a classifier to decode experienced level of pain
Test: can it generalise across people?
Specificity: can it distinguish physical pain from social pain?
Clinial relevance: can classifier detect action of pain-reducing drug?

11. Neural decoding of pain
Wager, T. D. et al., (2013). An fMRI-based neurologic signature of physical pain. New England Journal of Medicine, 368(15),

12. Different measures of accuracy (often used in medicine)
Positive Predictive Value and Precision are different names for the same thing

13. Neural decoder output scales with pain intensity
Wager, T. D. et al., (2013). An fMRI-based neurologic signature of physical pain. New England Journal of Medicine, 368(15),

14. Neural decoder discriminates pain from no-pain
Wager, T. D. et al., (2013). An fMRI-based neurologic signature of physical pain. New England Journal of Medicine, 368(15),

15. Distinguishing social from physical pain
Wager, T. D. et al., (2013). An fMRI-based neurologic signature of physical pain. New England Journal of Medicine, 368(15),

16. Key take-aways from class
fMRI can reveal help us to understand the structure of neural representations
“What lit up?” is no longer an interesting question
At its best, neuroimaging can provide information over and above what can be learned from behaviour