title: A two-layered diffusion model traces the dynamics of information processing in the valuation-and-choice circuit of decision making.
abstract: A circuit of evaluation and selection of the alternatives is considered a reliable model in neurobiology. The prominent contributions of the literature to this topic are reported. In this study, valuation and choice of a decisional process during Two-Alternative Forced-Choice (TAFC) task are represented as a two-layered network of computational cells, where information accrual and processing progress in nonlinear diffusion dynamics. The evolution of the response-to-stimulus map is thus modeled by two linked diffusive modules (2LDM) representing the neuronal populations involved in the valuation-and-decision circuit of decision making. Diffusion models are naturally appropriate for describing accumulation of evidence over the time. This allows the computation of the response times (RTs) in valuation and choice, under the hypothesis of ex-Wald distribution. A nonlinear transfer function integrates the activities of the two layers. The input-output map based on the infomax principle makes the 2LDM consistent with the reinforcement learning approach. Results from simulated likelihood time series indicate that 2LDM may account for the activity-dependent modulatory component of effective connectivity between the neuronal populations. Rhythmic fluctuations of the estimate gain functions in the delta-beta bands also support the compatibility of 2LDM with the neurobiology of DM.
authors.affiliation: Department of Medicine, Surgery & Neurosciences, University of Siena, Viale Bracci 2, 53100 Siena, Italy ; Eye-Tracking & Visual Application Lab, University of Siena, Viale Bracci 2, 53100 Siena, Italy.
authors.forename: Pietro
authors.identifier: 0000-0002-7504-1822
authors.initials: P
authors.lastname: Piu
authors.affiliation: Department of Medicine, Surgery & Neurosciences, University of Siena, Viale Bracci 2, 53100 Siena, Italy ; Eye-Tracking & Visual Application Lab, University of Siena, Viale Bracci 2, 53100 Siena, Italy.
authors.forename: Francesco
authors.identifier: 0000-0002-9643-9645
authors.initials: F
authors.lastname: Fargnoli
authors.affiliation: Department of Social, Political and Cognitive Sciences, University of Siena, Via Roma 56, 53100 Siena, Italy.
authors.forename: Alessandro
authors.identifier: 0000-0003-4550-4643
authors.initials: A
authors.lastname: Innocenti
authors.affiliation: Department of Medicine, Surgery & Neurosciences, University of Siena, Viale Bracci 2, 53100 Siena, Italy ; Eye-Tracking & Visual Application Lab, University of Siena, Viale Bracci 2, 53100 Siena, Italy.
authors.forename: Alessandra
authors.identifier: 0000-0002-2254-2869
authors.initials: A
authors.lastname: Rufa
mesh_terms: D003657:Decision Making; D001330:Electronic Data Processing; D006801:Humans; D008959:Models, Neurological; D009415:Nerve Net / Q000502:physiology*; D009474:Neurons; D017711:Nonlinear Dynamics