The name is absent

Membrane becomes re-polarized and may be hyperpolarized (overshoot).
Refractory period occurs while Na⁺ gates of the Na⁺ channels remain closed.
Membrane will not respond again until Na⁺ gates are active.

The ion currents in axons are greater than the currents in dendrites and the
neural impulse known as spike propagates without decrement. This is because
the ion channels in the axonal membrane are voltage gated and the current
propagation is non-linear. In the myelinated axons the spike jumps from node to
node of Ranvier (so called saltatory conduction). The myelin sheath is not
permeable for ions (the ion leakage across the membrane is thus prevented) and
indeed the sodium and potassium channels are clustered at the Ranvier nodes -
phenomenon that leads to increase of the conducting velocity!

Fig. 14 Axonal spike in myelinated neuron resulting from sodium and potassium
ion currents across the membrane in the nodes of Ranvier.

Higher stimulus intensity upon the nerve cell is reflected in increased frequency
of impulses, not in higher voltages: all action potentials look essentially the same.
The speed of propagation of the action potential for mammalian motor neurons is
10-120 m/s; while for nonmyelinated sensory neurons it's about 5-25 m/s

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