axon_sfap.mat

Axon SFAP data file

sfap~/sensitivity (name).mat contains the data for the axon single-fibre action potentials (aka single-unit field potentials) computed for a given axon population, fascicle pattern, and neural interface design. Generated by models.axon_sfap, used by plots.view_sfap.

The variables saved in a SFAP sensitivity.mat file are:

Variable	Type	Description
axons	struct array, 1 x nTypes	axon SFAP data for each simulated class, see below for details.
eidors_file	char	mesh and fields from which fascicle pattern and neural interface design was taken, as generated by models.nerve_anatomy
axons	struct array, 1 x nTypes	axon SFAP data for each simulated class
nerve	struct	nerve cross-sectional anatomy from axons.mat, as returned by mesh.insert_gmsh_fascicles at the time of axon population generation.
pop	struct array, 1 x nTypes	Data about each axon population. See axons.mat for details about the pop structure.
sam	struct	Data about the sampling of myelinated and unmyelinated axons into subtypes for simulation.

the axons structure:

Variable	Type	Description
axons.class	char	Name of the simulated class e.g. "Gaines (afferent)".
axons.time	double 1 x nTime	time vector (in ms) for recorded SFAPs.
axons.axon	struct	metadata about axon locations and subtypes extracted from pop
axons.sensitivity	struct array, nGroups x nFascicles	PCA components, weights, and variance explained for the first step of the SFAP calculation.
axons.component_SFAP	cell array, nGroups x nFascicles	computed waveforms for component description of axon-electrode coupling.
axons.units	struct	information about the units for each variable.
axons.axon_SFAP	double nTime x nChannels x nAxons	SFAP waveforms recorded on each electrode for each axon. By default the EIDORS file contains monopolar recording and stimulation fields, to enable easy post-hoc composition of complex stimuli or recording configurations, and so a 'channel' here refers to a monopolar recording on the corresponding electrode.