Associations between motor unit action potential parameters and surface EMG features

Motor Unit Action Potential Quantitation

The median frequency of the surface EMG power spectrum in relation to motor unit firing and action potential properties.

Three components determine the power spectrum of the surface EMG signal: the auto- and cross-power spectra of the firing processes and the power spectra of the motor unit action potential (MUAP). To clarify the relative contribution of these components to the median frequency (MF) of the power spectrum, a stochastic simulation model was used in which most input parameters [e.g., MUAP peak-peak ...

A simulation study for a surface EMG sensor that detects distinguishable motor unit action potentials.

An advanced volume conductor model was used to simulate the surface-detected motor unit action potentials (MUAPs) due to current sources located at different depths within the muscle tissue of the biceps brachii. Seven different spatial filters were investigated by linear summation of the monopolarly detected surface MUAPs on a square array of nine electrodes. The criterion of the relative ener...

Motor Unit Distribution Estimation by Multi- Channel Surface Emg

A new method for the non invasive estimation of motor unit distribution within the muscle is proposed. It is based on the surface EMG signal detected at different contraction levels in single differential configuration from an array of electrodes placed over the considered muscle in the direction orthogonal to the fibres.

Motor unit recruitment strategies investigated by surface EMG variables.

During isometric contractions of increasing strength, motor units (MUs) are recruited by the central nervous system in an orderly manner starting with the smallest, with muscle fibers that usually show the lowest conduction velocity (CV). Theory predicts that the higher the velocity of propagation of the action potential, the higher the power at high frequencies of the detected surface signal. ...