SIMULATION OF PNS MYELINATED AXON

This model is described in detail in:

McIntyre CC, Richardson AG, and Grill WM. Modeling the excitability of
mammalian nerve fibers: influence of afterpotentials on the recovery
cycle. Journal of Neurophysiology 87:995-1006, 2002.

The model is set up to reproduce part of Fig 2A from this paper.

This model can not be used with NEURON v5.1 as errors in the
extracellular mechanism of v5.1 exist related to xc. The original
stimulations were run on v4.3.1. NEURON v5.2 has corrected the
limitations in v5.1 and can be used to run this model.

Please contact mcintyre@bme.jhu.edu if you have any questions about
the model

20110523 rare condition bug fix supplied by Ted Carnevale where
vtrap2, 7, and 8 assignments in AXNODE.mod were fixed to prevent
discontinuity.

20141009 Nikki Pelot tidied up the code by changing e_pas = v_init to
e_pas = -80 in three lines (number 93, 106, 119) in MRGaxon.hoc.

20180920 NTC fixed stimulus parameter panel, 
which previously affected only stimulus amplitude.