All neurons work by sending signals in the form of impulses .
The cell membrane of a neuron is the key to the propagation of this signal. A stimulus changes this resting membrane potential into an action potential via depolarization . Myelin or a sheath made of lipid around the axon helps to conduct the nerve impulse more quickly. There is a junction or synapse to the dendrites of the next nerve cell. At a synapse, a nerve impulse will cause the release of a neurotransmitter from the presynaptic cell.