An opinion on the 'delayed spikes' in human motoneurons.

This is a note challenging the claim by Kudina and Andreeva's recent publication in Experimental Brain Research. In that publication, Kudina and Andreeva (Exp Brain Res 239:719-730, 2021) put forward a new idea about discovering two spiking modes in human motoneurons. We suggest that what they have shown in their publication maybe is the motor unit firing indicating the end of a net synaptic potential. We reason this challenge from our previous publication in the same journal. In that publication, we have shown that the "second spiking mode" after the H-reflex was a return to the regular prestimulus discharge rate.