Motoneuron simulations for counting motor units (Major and Jones 2005)

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Simulations of clinical methods to count the number of motoneurons/motor units in human patients. Models include stimulation of motor axons or voluntary activation and responses are measured as muscle tension or EMG.
1 . Major LA, Jones KE (2005) Simulations of motor unit number estimation techniques. J Neural Eng 2:17-34 [PubMed]
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Model Information (Click on a link to find other models with that property)
Model Type: Neuromuscular Junction;
Brain Region(s)/Organism:
Cell Type(s): Spinal cord lumbar motor neuron alpha ACh cell;
Gap Junctions:
Simulation Environment: MATLAB;
Model Concept(s): Simplified Models; Methods;
Implementer(s): Major, Lora [lora.major at];
Search NeuronDB for information about:  Spinal cord lumbar motor neuron alpha ACh cell;
function [muap] = muap2(isi,rtime,force)
%% [muap] = muap2(isi,rtime,force)
%% generate a 1st derivative gaussian MUAP, inputs are:
%%   isi = times of spikes
%%   rtime = time sequence for sim
%%   force = peak force for this mu
%%   muap time constant is uniform
%% output is muap = muap over the sim time

muap = zeros(size(rtime));

%% determine time of each spike
stime = isi(isi<rtime(end));

    [st,rt] = meshgrid(stime,rtime);
    offs = rt-st;
    %% muap function for each spike
    muapt = -sqrt(force)*offs.*exp((-offs.^2)/2) / sqrt(2*pi);
    muap = sum( muapt' ,1);

muap = muap(:);