The action potential is widely understood as an electrical phenomenon. However, a long experimental history has documented the existence of co-propagating mechanical signatures. Ahmed El Hady from the Princeton Neuroscience Institute and Benjamin Machta from the Lewis-Sigler institute have proposed a theoretical model to explain these phenomenon which they term Action Waves. In their model, these co-propagating waves are driven by changes in charge separation across the axonal membrane, just as a speaker uses charge separation to drive sound waves through the air. They argue that these forces drive surface waves involving both the axonal membrane and cytoskeleton as well as its surrounding fluid. Their model may help shed light on the functional role of the surprisingly structured axonal cytoskeleton that recent super-resolution techniques have uncovered, and suggests a wider role for mechanics in neuronal function.
Posted Mar 30 2015