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Published on: August 21, 2018
Spiral wave dynamics under feedback via an equilateral triangular sensory domain.
Somprasong Naknaimueang1, Michael A Allen, Stefan C Müller
1Institut für Experimentelle Physik, Otto-von-Guericke-Universität Magdeburg, Universitätplatz 2, D-39106 Magdeburg, Germany.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 7, 2007
Summary
Spiral wave core trajectories in excitable systems with triangular sensory domains exhibit unusual lobed limit cycles. These dynamics, observed numerically and experimentally, are characterized by express and stagnation zones.
Area of Science:
- Nonlinear Dynamics
- Complex Systems
Background:
- Spiral waves are fundamental patterns in excitable media.
- Understanding spiral wave dynamics is crucial in fields like biology and chemistry.
- Modulating excitability based on sensory input can alter wave behavior.
Purpose of the Study:
- To numerically investigate spiral wave core trajectories in systems with triangular sensory domains.
- To analyze the impact of domain shape and size on spiral wave behavior.
- To experimentally validate numerical findings using the Belousov-Zhabotinsky reaction.
Main Methods:
- Numerical simulations of spiral wave propagation in 2D excitable media.
- Modulation of system excitability based on integrated activity within a triangular sensory domain.
- Experimental studies using the light-sensitive Belousov-Zhabotinsky reaction.
- Introduction of express and stagnation zones for trajectory characterization.
Main Results:
- Unusual lobed limit cycles in spiral wave core trajectories were observed due to the triangular domain.
- These lobed cycles were found to be destroyed and re-formed upon variation of the domain size.
- Experimental results using the Belousov-Zhabotinsky reaction confirmed key numerical findings.
- The concept of express and stagnation zones effectively characterized observed trajectory behaviors.
Conclusions:
- The shape of the sensory domain significantly influences spiral wave core dynamics.
- Triangular domains can induce complex, non-trivial limit cycle behaviors.
- The express and stagnation zone concepts provide a useful framework for analyzing spiral wave trajectories in modulated systems.
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