A Discrete Model of Excitable Media

This Demonstration implements a model of excitable media. Space is represented as a grid of cells. Each cell can be in any of three states: (1) quiescent, (2) excited, or (3) refractory. A quiescent cell (white) becomes excited (green) if at least two of its neighbors are excited, then becomes refractory (yellow) at the next iteration. A refractory cell has a chance to become quiescent again with a fixed probability at every iteration.


  • [Snapshot]
  • [Snapshot]
  • [Snapshot]


Snapshot 1: the initial state of the model, which is mostly quiescent with randomly scattered excited cells
Snapshot 2: traveling waves emerging from disorder
Snapshot 3: a very long, steplike, moving structure
The "reset" button at the top right returns the model to its initial state. When the "run" checkbox is checked, the model runs continuously. When it is unchecked, the model does not run. Boundary conditions are periodic.
Based on a model discussed in [1].
[1] J. L. Schiff, Cellular Automata: A Discrete View of the World, New York: Wiley, 2008.
    • Share:

Embed Interactive Demonstration New!

Just copy and paste this snippet of JavaScript code into your website or blog to put the live Demonstration on your site. More details »

Files require Wolfram CDF Player or Mathematica.

Mathematica »
The #1 tool for creating Demonstrations
and anything technical.
Wolfram|Alpha »
Explore anything with the first
computational knowledge engine.
MathWorld »
The web's most extensive
mathematics resource.
Course Assistant Apps »
An app for every course—
right in the palm of your hand.
Wolfram Blog »
Read our views on math,
science, and technology.
Computable Document Format »
The format that makes Demonstrations
(and any information) easy to share and
interact with.
STEM Initiative »
Programs & resources for
educators, schools & students.
Computerbasedmath.org »
Join the initiative for modernizing
math education.
Step-by-Step Solutions »
Walk through homework problems one step at a time, with hints to help along the way.
Wolfram Problem Generator »
Unlimited random practice problems and answers with built-in step-by-step solutions. Practice online or make a printable study sheet.
Wolfram Language »
Knowledge-based programming for everyone.
Powered by Wolfram Mathematica © 2018 Wolfram Demonstrations Project & Contributors  |  Terms of Use  |  Privacy Policy  |  RSS Give us your feedback
Note: To run this Demonstration you need Mathematica 7+ or the free Mathematica Player 7EX
Download or upgrade to Mathematica Player 7EX
I already have Mathematica Player or Mathematica 7+