Improving electromyographic jitter measurements by analysis of the firing pattern

A new model for predicting the jitter from the firing pattern is presented. The jitter is decomposed into two components: 1) variation explained by the firing pattern, 2) random variation. The first component reflects the velocity recovery function of the muscle fiber. The second component reflects the neuromuscular transmission. Two methods are deduced from the model. Method I predicts the jitter from the most recent discharge. Method II can take any period of firing pattern into consideration. Model parameters can be given a physiological interpretation. Measures describing the velocity recovery function are derived. An improved estimate of the neuromuscular jitter is obtained compared to traditional jitter measures under simulated conditions.