Master Neuron Action Potential Propagation with Picmonic for Medicine

Neuron action potential propagation describes how the action potential generated at the axon hillock travels down the axon towards the nerve terminal. The depolarization wave is unidirectional, meaning signals can only travel down an axon and not back up. There is an absolute refractory period associated with the preceding sodium channels, which prevents depolarization of the same neuron region and channels from occurring rapidly. This allows for salt concentration gradients to be re-established. Neighboring voltage-gated channels open because of the initial sodium-influx, allowing for the depolarization and repolarization to propagate down the axon. They travel through the nodes of Ranvier, because these are non-insulated areas of the axon, and action potentials can only be generated at these locations. In general, the axon is myelinated, which provides insulation and increases propagation speed. The action potential jumping from a node of Ranvier to the next node is a form of transmission referred to as "saltatory conduction."