Variance as a Signature of Neural Computations during Decision Making

Churchland, A. K., Kiani, R., Chaudhuri, R., Wang, X. J., Pouget, A., Shadlen, M. N. (February 2011) Variance as a Signature of Neural Computations during Decision Making. Neuron, 69 (4). pp. 818-831.

Abstract

Traditionally, insights into neural computation have been furnished by averaged firing rates from many stimulus repetitions or trials. We pursue an analysis of neural response variance to unveil neural computations that cannot be discerned from measures of average firing rate. We analyzed single-neuron recordings from the lateral intraparietal area (LIP), during a perceptual decision-making task. Spike count variance was divided into two components using the law of total variance for doubly stochastic processes: (1) variance of counts that would be produced by a stochastic point process with a given rate, and loosely (2) the variance of the rates that would produce those counts (i.e., " conditional expectation" ). The variance and correlation of the conditional expectation exposed several neural mechanisms: mixtures of firing rate states preceding the decision, accumulation of stochastic " evidence" during decision formation, and a stereotyped response at decision end. These analyses help to differentiate among several alternative decision-making models.

Item Type: Paper
Subjects: bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > neurons
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > neurons
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > neurons
CSHL Authors:
Communities: CSHL labs > Churchland lab
Depositing User: Tom Adams
Date: 24 February 2011
Date Deposited: 16 Aug 2011 18:42
Last Modified: 05 Jan 2017 17:42
PMCID: PMC3066020
Related URLs:
URI: https://repository.cshl.edu/id/eprint/7749

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