Behavior- and Modality-General Representation of Confidence in Orbitofrontal Cortex

1. Behavior- and Modality-General Representation of
Confidence in Orbitofrontal Cortex
Paul Masset, Torben Ott, Armin Lak, Junya Hirokawa, Adam Kepecs
Current Literature: Vic Shao-Chih Chiang &
Jamie Beshore, 2021

2. ● “Thinking about thinking”
● Cognitive processes used in monitoring,
assessing behavior
● Prone to inaccuracies &
reliability problems
● Subjectivity makes it difficult to
study objectively
https://www.edutopia.org/blog/metacognition-gift-that-keeps-giving-donna-wilson-marcus-conyers
S. Fleming and R. Dolan (2012) Phil. Trans. R. Soc. B
What is metacognition?

3. ● Objective task paired with self-report
● Adaptations for animal studies
● Signal detection theory (SDT) -- decouples response bias and
sensitivity
● PFC implicated in metacognition
● brain injury and disease affecting PFC can cause changes to
metacognitive ability
S. Fleming and R. Dolan (2012) Phil. Trans. R. Soc. B
How can we measure metacognition?

4. S. Fleming and R. Dolan (2012) Phil. Trans. R. Soc. B
Dissociating task performance from metacognition

5. ● rlPFC (& other areas of PFC) at the top of a hierarchy in integrating
● Also some independent signal for representing and manipulating
internally generated information
● A current hypothesis: metacognitive ability is socially adaptive
Social Role?

6. M. Dixon et al. K. Christoff (2017) Psychological Bulletin

7. Do OFC neurons signal abstract decision confidence?
1. Neural activity = statistical decision confidence
2. Predictive of choice
3. Abstract and centralized representation
P Masset et al. A Kepecs (2020) Cell
Present study

8. Behavioral paradigm
P Masset et al. A Kepecs (2020) Cell

9. P Masset et al. A Kepecs (2020) Cell
Psychometric curves

10. Time investment behavior consistent with decision confidence models
P Masset et al. A Kepecs (2020) Cell
E F G

11. Potential confounds
● Could be intuitively similar processes at play, e.g., attention
● These signals do not by themselves satisfy all 3 signatures
● These signals probably act more like a gain than a reproduction
of confidence
J. Sanders (2014) PhD Thesis

12. P Masset et al. A Kepecs (2020) Cell
Choice and confidence prediction model

13. P Masset et al. A Kepecs (2020) Cell
Estimating confidence mapping function

14. P Masset et al. A Kepecs (2020) Cell
Choice and confidence prediction model

15. TA Stalnaker, NK Cooch, G Schoenbaum (2015) Nat Neurosci
• S-O: stimulus outcome
• OFC: orbitofrontal cortex
Orbitofrontal Cortex

16. Orbitofrontal cortex neurons are tuned to
decision confidence
• Sp/s: spikes per second
P Masset et al. A Kepecs (2020) Cell

17. Confidence neuron
subtypes generalize
outcome prediction across
sensory modalities
• OPI: outcome predictive index
• R: regression
P Masset et al. A Kepecs (2020) Cell

18. Reinforcement
learning model
P Masset et al. A Kepecs (2020) Cell
• P: probability that a choice is
rewarded
• L: left
• R: right
• Q: action values
• V: cached values
• Qchoice : choice values
• α: learning rate
• Δ: prediction error
• r: reward

19. Confidence-guided choice updating
P Masset et al. A Kepecs (2020) Cell
• P: probability

20. Orbitofrontal cortex neurons in choice updating
P Masset et al. A Kepecs (2020) Cell
• Repeat: probability of
repeating the same choice
• k: trial
• f: logistic function
• β0: constant term
• β1:evidence for choice
• β2: previous trial’s evidence
• β3: average firing rate of
neuron
• P: probability
• A: auditory
• O: olfactory

21. Single-cell RNA sequencing of activated
confidence(+) neurons with FLiCRE?
CK Kim et al. AY Ting (2020) Biorxiv
• FLiCRE: Fast Light & Calcium-
Regulated Expression
• MKII: calmodulin-binding peptide
• LOV: evolved light-oxygen-voltage
photosensory domain
• Gal4: transcription factor
• TEV: tobacco etch virus
• uTEVp: truncated TEV protease
• TEVcs: TEV cleavage site
• UAS: upstream activating
sequence
• CD4: cluster of differentiation 4

22. Manipulating
confidence(+) neuron
activity during
decision-making with
non-invasive
optogenetics SOUL?
X Gong et al. GP Feng (2020) Neuron
• SOUL: step-function opsin with ultra-
high light sensitivity
• LH: lateral hypothalamus

23. Summary
P Masset et al. A Kepecs (2020) Cell

24. JI Sanders et al. A Kepecs (2016) Neuron
Statistical
decision
confidence in
primates?
Blackboard Comments

25. A Lak et al. A Kepecs (2014) Neuron
Is statistical decision confidence strictly in the OFC?
Blackboard Comments
• WT: waiting time
• AP: anterior-posterior
• Ctrl: control
• Mus: muscimol

26. Taking accuracy out of the equation?
Blackboard Comments
P Masset et al. A Kepecs (2020) Cell
• β: coefficient
• t: time
• TI: time investment
• R: firing rate
• r: regression
• FR: firing rate
• Olf: olfactory
• Aud: auditory