@ Decision Neuroscience Scott Huettel, Duke University The Neural Representation of Decision- Making under Uncertainty Scott Huettel Psychology & Neuroscience Duke University

@ Decision Neuroscience Scott Huettel, Duke University “…there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns -- the ones we don't know we don't know.” - Rumsfeld (2003, in press)

@ Decision Neuroscience Scott Huettel, Duke University “To preserve the distinction… between the measurable uncertainty and an unmeasurable one we may use the term ‘risk’ to designate the former and the term ‘uncertainty’ for the latter. … It is this [type of] uncertainty which has been neglected in economic theory, and which we propose to put in its rightful place.” F. H. Knight (1921) Risk, Uncertainty, & Profit

@ Decision Neuroscience Scott Huettel, Duke University Outline of the Talk Uncertainty defined Case study: Ambiguity –Contributions of lateral prefrontal, parietal cortex? –Contributions of orbitofrontal cortex, amygdala? Discussion: What should neuroscience seek?

@ Decision Neuroscience Scott Huettel, Duke University “Information occurs only if there exists some a priori uncertainty, and the amount of information is determined by the amount of the uncertainty – or, more exactly, it is determined by the amount by which the uncertainty has been reduced.” - Garner (1962). Uncertainty and Structure as Psychological Concepts, p. 3. Wendell “Tex” Garner

@ Decision Neuroscience Scott Huettel, Duke University

LPFC Huettel, Mack, & McCarthy (2002) Nature Neuroscience BOLD Signal Change Sequence Length Lateral PFC LPFC

@ Decision Neuroscience Scott Huettel, Duke University McCoy & Platt (2005) Nat Neuro Ubiquitous Risk Signals Preuschoff et al. (2007) J Neurosci Insula Huettel et al. (2005) J Neurosci Parietal Cortex Prefrontal Cortex Posterior Cingulate

@ Decision Neuroscience Scott Huettel, Duke University From Glimcher & Rustichini (2004) Science.

@ Decision Neuroscience Scott Huettel, Duke University Risky - CertainAmbiguous - CertainRisky - RiskyAmbiguous - Risky Trial Types Trial Structure Decision (RT) Expectation (4.5-6s) Outcome (2s) Huettel et al. (2006) Neuron Risk vs. Ambiguity

@ Decision Neuroscience Scott Huettel, Duke University pPAR LPFC aINS LPFC Signal change (%) 0.12 BOLD Parameters (a.u.) 20 ACARRCRR AC ARRCRR Time since trial onset (s) aINS pPAR ACARRCRR Trial Type 20 L

@ Decision Neuroscience Scott Huettel, Duke University Risk: Expected UtilityAmbiguity: α – MaxMin Expected Utility Ambiguity Preferring Risk Preferring Ambiguity Averse Risk Preferring Ambiguity Preferring Risk Averse Ambiguity Averse Risk Averse Subjects (n=13)

@ Decision Neuroscience Scott Huettel, Duke University Ambiguity Preference (AC + AR) – (RC + RR) Ambiguity preference (1-α)Risk preference (β) (RC + RR) - (AC + AR) Risk Preference LPFC aINS pPAR More (1)(0) Less More (3) (0) Less α - Ambiguityβ - Risk Correlation with Economic Preference Resampling Analysis LPFC Ambiguity… in Lateral Prefrontal Cortex?

@ Decision Neuroscience Scott Huettel, Duke University Hsu et al. (2005) Science Ambiguity… in Orbitofrontal Cortex?

@ Decision Neuroscience Scott Huettel, Duke University Evidence from Cognitive Neuroscience Lateral prefrontal cortex –Important for establishing rules for behavior –Implicated in reasoning, response selection Orbitofrontal cortex –Important for learning about (aversive) stimuli –Implicated in inhibition of behavior

@ Decision Neuroscience Scott Huettel, Duke University Interim Take-Home Message Concepts from decision science are unlikely to reflect unitary psychological constructs nor single neural modules

@ Decision Neuroscience Scott Huettel, Duke University Conditioning of Risk and Ambiguity Bach et al. (2009) J Neurosci Here, ambiguity reflects the expected revelation of information; i.e., a potentially known unknown.

@ Decision Neuroscience Scott Huettel, Duke University Stimuli involving ambiguity evoked greater activation in dlPFC and PPC than those involving risk or ignorance. Bach et al. (2009) J Neurosci

@ Decision Neuroscience Scott Huettel, Duke University pIFS Huettel & Misiurek (2004) In a task similar to an implicit Wisconsin Card Sorting Task (i.e., learning rules without immediate feedback)… …stimuli that eliminate potential rules evokes activation in lateral PFC (the posterior inferior frontal sulcus)… …proportional to the # eliminated rules.

@ Decision Neuroscience Scott Huettel, Duke University Ventral PFC Damage Increases Risk Seeking Clark et al. (2008) Brain Cf. Goel et al. (2007) Cerebral Cortex, who argue for potential laterality effects in reasoning: RH impairs under incomplete information

@ Decision Neuroscience Scott Huettel, Duke University Kringelbach (2005) Nat. Rev. Neurosci Hsu et al. (2005) Science Punishment / Aversion Plassmann et al. (2007) J. Neurosci. Reward / Value

@ Decision Neuroscience Scott Huettel, Duke University LPFC Huettel et al. (2006) Neuron Hsu et al. (2005) Science Ambiguity effects in orbital PFC –Tasks (3): Gambles, knowledge, opponent –Activation preceded decision (slow) –Aversion led to increased activation –Subject sample: very ambiguity averse Ambiguity effects in lateral PFC –Task (1): Gambles –Activation coincident with decision (fast) –Aversion led to decreased activation –Subject sample: ambiguity neutral Emotional aversion signal: pushes behavior away from ambiguous/risky options? Cognitive signal: supports creation of decision scenario under ambiguity?

@ Decision Neuroscience Scott Huettel, Duke University A Lesson from Psychology… for Neuroeconomics? “A concept that is synonymous with a single operation is nothing more than a restatement of an experimental result. But a concept that arises as a consequence of converging operations has a reality that is independent of any single experimental observation. “But before we can get convergence, we must introduce variation in our experimental procedures. … Stabilizing on a few techniques… [is] utterly self-defeating… because it completely drops the critical part from critical realism.” The Processing of Information and Structure p. 187 Wendell “Tex” Garner

@ Decision Neuroscience Scott Huettel, Duke University Acknowledgments Support NIMH, NINDS, NIA Duke Institute for Brain Sciences Laboratory Members McKell Carter Chris Coutlee John Clithero Debra Henninger O. Mullette-Gillman Brandi Newell Allison Scott David Smith Adrienne Taren Vinod Venkatraman Richard Yaxley neuroeconomics.duke.edu Collaborators on these Projects Gregory McCarthy Michael Platt