Neural encoding of decision uncertainty in prefrontal cortex
-
1
Baylor College of Medicine, United States
Uncertainty is ubiquitous in perception and decision making and makes inference particularly difficult (e.g. object categorization). Therefore, understanding how the brain represents and computes with uncertain information is a fundamental quest in neuroscience. Sensory data come with bottom-up uncertainty since they are corrupted by noise. Decisions are typically made by combining bottom-up sensory information with prior or top-down knowledge learned from the past. To achieve statistically optimal (or Bayes-optimal) behavior it is necessary for the brain to represent all these sources of uncertainty and combine them appropriately. Behavioral studies have demonstrated that humans perform close to Bayes-optimally when combining multiple sensory cues about an underlying stimulus, supporting the hypothesis that the brain represents and computes with probability distributions. However, the neural mechanisms used by the brain to compute under uncertainty remain elusive. We studied if top-down uncertainty was encoded in the prefrontal cortex. We have trained a monkey in a probabilistic classification task. The orientation of a stimulus (drifting grating) was drawn from one of two overlapping probability distributions. The animal had to infer from which class the stimulus came, although this could often not be determined with certainty. We recorded single-unit activity from the PFC using tetrodes while the monkey performed this task. We found that neurons not only encoded the class decision of the animal but PFC activity was also correlated with the posterior probability of class (i.e. class certainty). Specifically, neurons that preferred class A increased their firing when the probability of class A given the stimulus orientation was higher. PFC neurons also exhibited this effect during the delay period when the animal was required to remember its decision in the absence of the stimulus. Thus, we demonstrate that the PFC, a brain area thought to be at the peak of the decision-making hierarchy, encodes relevant probabilities associated with the inference problem the brain is solving.
Conference:
Computational and Systems Neuroscience 2010, Salt Lake City, UT, United States, 25 Feb - 2 Mar, 2010.
Presentation Type:
Poster Presentation
Topic:
Poster session I
Citation:
Cotton
JR,
Laudano
A and
Tolias
AS
(2010). Neural encoding of decision uncertainty in prefrontal cortex.
Front. Neurosci.
Conference Abstract:
Computational and Systems Neuroscience 2010.
doi: 10.3389/conf.fnins.2010.03.00027
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
18 Feb 2010;
Published Online:
18 Feb 2010.
*
Correspondence:
James R Cotton, Baylor College of Medicine, Houston, United States, rcotton@cns.bcm.edu