We can clearly see the effects of the breakdown of the decision-making system of the brain in three phenomenon: Craving, Denial, and Pleasure-blindness.
Craving describes both the physical compulsion to drink and the mental obsession about drink. The alcoholic's life revolves around alcohol. Even when she is functioning in a fairly normal way, i.e. taking care of normal daily tasks, she is still thinking about alcohol. This obsession may take the form of longing and planning for the next drink or binge, or even wrestling with the desire to not drink. It's all a form of craving.
Most people use the word craving to describe a desire for chocolate for example. The craving in addiction is much more severe, overwhelming, and debilitating. Imagine not eating for three days and then trying not to think about food. At that point, your midbrain would be screaming for food! The addict has the same obsession with his drug, every day, because the midbrain has declared the drug to be #1.
Denial is often the most maddening part of addiction to the outsider. Everyone around the alcoholic sees the bad behavior and bad consequences. The alcoholic often does not see it that way at all, or, if she does, only fleetingly and through a haze. Denial is why the alcoholic is usually the last person to recognize the depth and seriousness of a problem.
Again, this is a reflection of what is happening in the brain. The pleasure circuitry of the brain is desperately trying to protect its unobstructed access to the drug. Alcoholics often appear to have a relationship with alcohol, as if it is their best friend. Essentially that is what their brains are telling them.
Pleasure blindness (anhedonia) is the inability to enjoy formerly pleasurable experiences. Alcoholics can get to the point where they feel depressed and utterly numb to ordinary and important pleasures; like family, hobbies, art, music, and beauty in nature.
Those on the outside are painfully puzzled as to why their loved one no longer seems to take joy in them or anything truly worthwhile.
This is an outward reflection of the twisted inner chemistry of the addicted brain. In a normal brain, typical dopamine surges, such as enjoying a granddaughter, "reach" the pleasure set-point and register as enjoyable events. However, repeated dopamine floods from drinking or using drugs raise the set-point so impossibly high that only the drug provides any sense of fleeting pleasure. Ironically, in later addiction no amount of alcohol brings pleasure. The alcoholic then begins to drink in a desperate attempt to feel normal (e.g. vodka in the morning coffee to stop jitters and get moving), or simply to feel nothing.
So again, we can see how lower brain dysfunctions have compromised the higher functions of choice. The prefrontal cortex, that executive part of the brain that polishes our humanity, has been set aside.