>>11172916An electrolyte is a molecule which "breaks" into two molecules/atoms when put in a solvent, one is charged positively, one is charged negatively (cations and anions). These charges cancel each other when you let them together.
If you expose the solution to a current (basically two points with a difference of charge, creating a field) then the ions will move in the solutions and be attracted to the points with an opposite charge to theirs (as they want to cancel it). This movement is called a current.
Now at their base state the inside of neurons is dominated by anions (-) compared to the outside which is more balanced. These excess anions stuck themselves on the membranes (because they seek to neutralize each others but are blocked by the membrane) attracting cations on the other side as a result the membrane has two poles: a negative inside and a positive outside, it's called a "potential" (because it has the potential to create current if both poles are "bridged").
Now when a neuron activates there is an outside neurotransmitter fixing a receptor on its membrane, as a result the membrane opens some little canals, some cations and anions become free to neutralize each others and the poles weaken (the reason why it's called depolarization). This change of potential in one location provokes a domino effect on the rest of the membrane which opens more canals which depolarize at their turn, etc... Up to the other side of the neuron where this change of potential provokes the liberation of a neurotransmitter which will activate another neuron in the same fashion.
This chain continues up to the last neuron.
