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Reentry

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\nAuthor: Anton Prassl anton.prassl@medunigraz.at\n\ <h2 id=\"tutorial_extracellular-stimulation\">Extracellular stimulation\n

Transmembrane\ \ voltage can be changed by applying an extracellular field in the extracellular\ \ space. As outlined in Sec. <code class=\"interpreted-text\" role=\"ref\">electrical-stimulation,\ \ an electric field can be set up either by injection/withdrawal of currents in\ \ the extracellular space or by changing the extracellular potential with voltage\ \ sources.

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For testing the various types of extracellular stimulation we\ \ generate a thin strand of tissue of 1 cm length. Electrodes are located at both\ \ caps of the strand with an additional auxiliary electrode in the very center of\ \ the strand. An illustration of the setup is given in <code class=\"interpreted-text\"\ \ role=\"numref\">fig-extra-stim-setup. Extracellular voltage and current\ \ stimuli are pre-configured to generate an extracellular voltage drop across the\ \ strand of about 2 V. This corresponds to an electric field magnitude of 2 V/cm\ \ which is sufficient to initiate action potential propagation under the cathode.

\n\ <div id=\"fig-extra-stim-setup\">\n
\n<img src=\"20_reentry/ExtracellularStimulationSetup.png\"\ \ class=\"align-center\" style=\"width:50.0%\" alt=\"\" />
Simple setup\ \ for testing the various configurations for extracellular stimulation. Three electrodes\ \ are pre-defined, electrode A and B located at the left hand face and right hand\ \ face of the tissue strand, respectively, and an additional auxiliary electrode\ \ C sitting on top of the strand in its center.
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\n\n\ <h2 id=\"experiments\">Experiments\n

Several types of stimulation setups\ \ are predefined. To run these experiments

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cd ${TUTORIALS}/02_EP_tissue/02_stimulation
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Run

20_parameter_sweep