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Table 1 Glossary of parameters and variables

From: Linking demyelination to compound action potential dispersion with a spike-diffuse-spike approach

Variable Name Units
β Stochastic scaling mV−1
\(\delta T_{i}\) Internodal delay in units of membrane time constant
\(\delta T_{N}\) Internodal delay for whole axon
\(\delta T_{TP}\) Mean internodal delay for whole axon and averaged across lesion configurations
ϕ Normaliozed extracellular potential
θ Stochastic threshold mV
γ Ratio of length constants
\(\lambda_{i} \) Electrotonic length constant of ith internode mm
\(\lambda_{M}\) Electrotonic length constant of a myelinated segment mm
\(\lambda_{D}\) Electotonic length constant of a damaged segment mm
\(\lambda_{L}\) Electrotonic length constant of a fully demyelinated segment mm
\(\rho_{i}\) Firing hazard of node i
\(\sigma^{2}_{TP}\) Variance of transmission delay across lesion configurations
\(\sigma_{e}\) Electric permittivity
τ Membrane time constant ms
D Internodal distance in units of electrotonic length constant
\(G_{i}(T,X)\) Green’s function of internodal propagation mV / pA
\(I_{\mathrm{AP}}\) AP current influx pA
k Lesion size Number of internodes
\(N_{ij}\) Number of nodes in configration ij
\(N_{L}\) Total number of lesions
Mean number of lesions
\(p_{L}\) Frequency of lesions Lesions per node
\(P_{T}^{(i)}\) Probability of transmission across internode i
\(P_{T}^{(\mathrm{axon})} \) Probability of transmission across whole axon
\(p_{i}(T,X)\) Probability of firing first spike at node i 
\(T_{i}\) Time of action potential in node i and in units of membrane time constant
t Time from action potential ms
\(V_{i}(T,X)\) Membrane potential deflection along internode i mV
v Propagation speed m/s
X Distance along internode in units of electrotonic constant
x Distance along internode mm