Abstract As one of the most complex systems known to science, modeling brain behavior and function is both fascinating and extremely difficult. Empirical data is increasingly available fromex vivohuman brain organoids and surgical samples, as well asin vivoanimal models, so the problem of modeling the behavior of large-scale neuronal systems is more relevant than ever. The statistical physics concept of a mean-field model offers a tractable way to bridge the gap between single-neuron and population-level descriptions of neuronal activity, by modeling the behavior of a single representative neuron and extending this to the population. However, existing neural mean-field methods typically either take the limit of small interaction sizes, or are applicable only to the specific neuron models for which they were derived. This paper derives a mean-field model by fitting a transfer function called Refractory SoftPlus, which is simple yet applicable to a broad variety of neuron types. The transfer function is fitted numerically to simulated spike time data, and is entirely agnostic to the underlying neuronal dynamics. The resulting mean-field model predicts the response of a network of randomly connected neurons to a time-varying external stimulus with a high degree of accuracy. Furthermore, it enables an accurate approximate bifurcation analysis as a function of the level of recurrent input. This model does not assume large presynaptic rates or small postsynaptic potential size, allowing mean-field models to be developed even for populations with large interaction terms. 
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                            A Behavior-Based Population Tracker Can Parse Aggregate Measurements to Differentiate Agents
                        
                    
    
            Closed-loop state estimators that track the movements and behaviors of large-scale populations have significant potential to benefit emergency teams during the critical early stages of disaster response. Such population trackers could enable insight about the population even where few direct measurements are available. In concept, a population tracker might be realized using a Bayesian estimation framework to fuse agent-based models of human movement and behavior with sparse sensing, such as a small set of cameras providing population counts at specific locations. We describe a simple proof-of-concept for such an estimator by applying a particle-filter to synthetic sensor data generated from a small simulated environment. An interesting result is that behavioral models embedded in the particle filter make it possible to distinguish among simulated agents, even when the only available sensor data are aggregate population counts at specific locations. 
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                            - Award ID(s):
- 1903972
- PAR ID:
- 10147565
- Date Published:
- Journal Name:
- IEEE Homeland Security Technologies (HST 2019)
- Page Range / eLocation ID:
- 1 to 5
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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