Action potential propagation in space and time

Understanding how action potential propagation in muscle fibres can be assessed from surface EMG

This material was prepared with the goal of illustrating how surface EMGs convey information on the propagation of action potentials.  Analogy is made to the wave generated by dropping a rock on a water tank.  The propagation of the water wave generated when the rock hits the water surface can be assessed by measuring the height of multiple floating objects positioned serially along the water.  Similarly, the propagation of action potentials generated at the end plates can be assessed by measuring the surface, electric potential with electrodes positioned consecutively along the skin.

 

About the Author

Alberto Botter

Alberto Botter

Laboratory for Engineering of the Neuromuscular System, Politecnico di Torino, Italy

Ph.D. in Biomedical Engineering (2011). He is currently Associate Professor in Biomedical Engineering at Politecnico di Torino. His research interests include neuromuscular electrical stimulation, surface EMG, electrode technology, and signal processing applied to biomedical signals.

COPYRIGHT

(c) 2023 by the author. Except as otherwise noted, the ISEK Teaching Repository, including its text and figures, is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License. To view a copy of this license, visit https://creativecommons.org/licenses/by-sa/4.0/legalcode.

You May Also Like…

Muscle force regulation

Muscle force regulation

Passive and active mechanisms determine the net, muscle force.  The latter is associated with the number of muscle fibers excited, and thus motor units recruited, and the rate at which muscle fibers are excited.  The first three slides provide an approximate...

HD-EMG and action potential propagation

HD-EMG and action potential propagation

The muscle fibre conduction velocity (CV) is the speed with which action potentials travel along the muscle fibres. Owing to its sensitivity to events of applied interest (e.g. muscle fatigue), CV earns relevance for the study of the neuromuscular system. The...

EMG and innervation of external anal sphincter

EMG and innervation of external anal sphincter

Innervation zones, where end-plates distribute within striated muscles, can be identified with arrays of electrodes.  For this to be possible, electrodes and muscle fibres must reside in parallel planes.  Innervation zones are identified where two, consecutive action...