Alcohol is a psychoactive substance, which means that it produces changes in the way our brains behave. This is most readily observable with a state of intoxication during which our mood, behavior, and cognitive abilities are temporarily altered. Over time, however, chronic exposure to alcohol produces long-lasting or even permanent changes in brain function, in a process called neuroadaptation, as our brains accommodate the effects of alcohol exposure. This is what is known as alcohol dependence; your brain has come to depend on alcohol to maintain equilibrium. If alcohol is suddenly discontinued at this point, you can experience uncomfortable and even dangerous observable and non-observable alcohol withdrawal symptoms as your brain struggles to regain stability.