What causes alcohol addiction?

Alcohol use produces alteration of some substance that form one person's brain structure, like gamma-aminobutric acids (which produces inhibition), glutamate (which produces nervous system excitability) or dopamine which gives the pleasant sensation when drinking. Time, after time, the equilibrium in generally broken, so that the organism gets to a point in which it demands alcohol to deal with some physical states.

This way, dependence appears, but it may also be produced by other elements: