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arXiv · 1802.01627

Sensitivity of asymmetric rate-dependent critical systems to initial conditions: insights into cellular decision making

Nuno R. Nené·James Rivington·Alexey Zaikin
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Abstract

The work reported here aims to address the effects of time-dependent parameters and stochasticity on decision-making in biological systems. We achieve this by extending previous studies that resorted to simple normal forms. Yet, we focus primarily on the issue of the system's sensitivity to initial conditions in the presence of different noise distributions. In addition, we assess the impact of two-way sweeping through the critical region of a canonical Pitchfork bifurcation with a constant external asymmetry. The parallel with decision-making in bio-circuits is performed on this simple system since it is equivalent in its available states and dynamics to more complex genetic circuits. Overall, we verify that rate-dependent effects are specific to particular initial conditions. Information processing for each starting state is affected by the balance between sweeping speed through critical regions, and the type of fluctuations added. For a heavy-tail noise, forward-reverse dynamic bifurcations are more efficient in processing the information contained in external signals, when compared to the system relying on escape dynamics, if it starts at an attractor not favoured by the asymmetry and, in conjunction, if the sweeping amplitude is large.

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Nuno R. Nené, James Rivington, Alexey Zaikin. 2018-02-05. Sensitivity of asymmetric rate-dependent critical systems to initial conditions: insights into cellular decision making. https://doi.org/10.1103/physreve.98.022317

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