"... To help decipher the biophysical basis for ‘paroxysmal’
spiking, we replicated afterdischarge (i.e. continued spiking after a brief stimulus) in a
minimal conductance-based axon model.
...
A perturbation
could abruptly switch the system between two (quasi-)stable attractor states: rest and
repetitive spiking.
...
Initiation of afterdischarge was explained by activation of the
persistent inward current forcing the system to cross a saddle point that separates the basins of
attraction associated with each attractor.
Termination of afterdischarge was explained by the
attractor associated with repetitive spiking being destroyed.
...
The model also explains other features of
paroxysmal symptoms, including temporal summation and refractoriness."
The NEURON and XPP code is available for the paper:
Coggan JS, Ocker GK, Sejnowski TJ, Prescott SA (2011) Explaining pathological changes in axonal excitability through dynamical analysis of conductance-based models. J Neural Eng 8:065002
from the authors and at the authors web site:
http://prescottlab.ca/code-for-models
as well as in this modeldb archive. The XPP code is the ode file in the top-level folder and the NEURON code is in the NEURONcode folder.
The XPP file was contributed by Steve Prescott and the NEURON code was contributed by Jay Coggan.