Optimal Decisions: From Neural Spikes, through Stochastic Differential Equations, to Behavior

Philip HOLMES
Eric SHEA-BROWN
Jeff MOEHLIS
Rafal BOGACZ
Juan GAO
Gary ASTON-JONES
Ed CLAYTON
Janusz RAJKOWSKI
Jonathan D. COHEN

Publication
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences   Vol.E88-A    No.10    pp.2496-2503
Publication Date: 2005/10/01
Online ISSN: 
DOI: 10.1093/ietfec/e88-a.10.2496
Print ISSN: 0916-8508
Type of Manuscript: Special Section INVITED PAPER (Special Section on Nonlinear Theory and its Applications)
Category: 
Keyword: 
stochastic differential equations,  drift-diffusion process,  dynamical systems,  phase oscillators,  decision-making models,  

Full Text: PDF(603.3KB)>>
Buy this Article



Summary: 
There is increasing evidence from in vivo recordings in monkeys trained to respond to stimuli by making left- or rightward eye movements, that firing rates in certain groups of neurons in oculo-motor areas mimic drift-diffusion processes, rising to a (fixed) threshold prior to movement initiation. This supplements earlier observations of psychologists, that human reaction-time and error-rate data can be fitted by random walk and diffusion models, and has renewed interest in optimal decision-making ideas from information theory and statistical decision theory as a clue to neural mechanisms. We review results from decision theory and stochastic ordinary differential equations, and show how they may be extended and applied to derive explicit parameter dependencies in optimal performance that may be tested on human and animal subjects. We then briefly describe a biophysically-based model of a pool of neurons in locus coeruleus, a brainstem nucleus implicated in widespread norepinephrine release. This neurotransmitter can effect transient gain changes in cortical circuits of the type that the abstract drift-diffusion analysis requires. We also describe how optimal gain schedules can be computed in the presence of time-varying noisy signals. We argue that a rational account of how neural spikes give rise to simple behaviors is beginning to emerge.


open access publishing via