Conduction of impulses by a neuron is a combined result of various mechanical, chemical, and electrical disturbances that take place when a neuron is excited by a stimulus.
Impulse is defined as an electrochemical event governed by the differential permeability of neurilemma to sodium and potassium ion.
When the neurons are in a resting state, the extracellular space of the neurons remains comparatively electropositive than the cytoplasm of the cell.
This condition where the outside of a nerve cell has a greater positive charge than the inside of the cell is termed the polarized state of the neuron.