The Anatomy of Addiction (7 page)

Not only does overstimulation of the reward circuitry factor significantly in addiction but it also creates false memories of the experience. The brain regards the experience as “better than expected,” even when the experience wasn't all that great. Because the memory is a permanent part of your mental makeup, anything and everything that reminds you of that memory also reminds you that the experience was better than expected and triggers an instant desire to reexperience something that perhaps wasn't anywhere as good as you remember.

Sound twisted and illogical? Well, it is! Welcome to the world
of addicts and alcoholics who, no matter how bright they are, rely on a brain that is constantly giving them false signals.

However, an addict doesn't even have to ingest a substance to flip the trigger. An alcoholic can pass a bar and the mere association of the booze inside can create a cascade of anxiety that mimics the feelings of withdrawal. That's why many drug addicts and alcoholics relapse. The craving never disappears. It's always there. It's like every other chronic disease in the sense that the disease is never cured.

The difference between addiction and most other chronic diseases is that it affects the brain. That's important because, as previously mentioned, the brain controls behavior, so a disease of the brain will have behavioral consequences. Because of these brain changes, people become unable to make conscious decisions in their own best interest. The medically accepted definition of addiction clearly states that the individual thus afflicted will compulsively pursue a detrimental course of action, despite continual negative health and social consequences.

Once the brain change has taken place, medical treatment coupled with intentional behavior modification can help restore balance, and in some cases, actually repair damage to the brain's reward circuitry. To make things really clear, here is a useful, if perhaps an oversimplified, formula:

GP
+
ES
=
A

Genetic predisposition (
GP
) + Excessive stimulation of the pleasure–reward pathway (
ES
) = Addiction (
A
)

Therefore, for someone with a genetic predisposition to addiction, an effective preventive measure is a diversity of pleasures,
none of them to excess. Knowing that too much pleasure repeated too often, especially from a singular source, is a major factor in addiction, the wise person practices moderation, enjoys a variety of different activities, and guards against overdoing any one thing.

Addiction is characterized by the inability to consistently abstain, by impairment in behavioral control, by cravings, by diminished recognition of significant problems with one's behaviors and interpersonal relationships, and by a dysfunctional emotional response. Like other chronic diseases, addiction often involves cycles of relapse and remission. Without treatment or engagement in recovery activities, addiction is progressive and can result in disability or premature death.

With addiction, there is a significant impairment in executive functioning (the part of the brain that organizes and acts on information), which manifests in problems with perception, learning, impulse control, compulsivity, and judgment. People with addiction often manifest a lower readiness to change their dysfunctional behaviors, despite mounting concerns expressed by significant others in their lives. They also display an apparent lack of appreciation of the magnitude of cumulative problems and complications.

The still developing frontal lobes of adolescents, in particular, may both compound these deficits in executive functioning and predispose youngsters to engage in high-risk behaviors, including alcohol or other drug use. The profound drive or craving to use substances or engage in apparently rewarding behaviors underscores the compulsive aspect of this disease. This is the connection with “powerlessness” over addiction and “unmanageability” of life, as is described in the first step of 12-step programs.

The Effects of Alcohol on the Brain

It's at this point where we must stop thinking of drug and alcohol addiction as synonymous. In terms of its physiological effect on the body and its consequences to the health of the addict, alcohol is much more insidious and its damage more serious.

Despite alcohol consumption being both socially acceptable and perfectly legal, it kills more people than any other drug in the United States. Alcohol is the third leading cause of death, because it attacks every vital organ system in the human body. Yet, the fact that it is legal—even celebrated and glamorized—makes it far more acceptable than, say, crack in modern society. Keep in mind that at the advent of the twentieth century both cocaine and heroin were sold as over-the-counter medications, and wealthy white women were more likely to be addicted to drugs, including morphine, than any other group in the country. (Celebrated early twentieth-century American playwright Eugene O'Neill made repeated references to his mother's morphine addiction in plays such as
Long Day's Journey into Night
.)

The physical effects of alcohol addiction are far more widespread than addiction to drugs. Alcohol directly or indirectly causes stomach cancer, rectum cancer, colon cancer, throat cancer, liver cancer, larynx cancer, and esophageal cancer. Alcohol doesn't cause lung cancer, but as many alcoholics also smoke, you might take that into consideration as well.

Scientists used to think of alcohol as a membrane disruptor with a generalized effect all over the brain, as the small molecule can freely diffuse across the blood–brain barrier. We now know that there are particular cells in the brain that alcohol
targets by binding certain hydrophobic pockets on their surface receptors.

Unlike opioids (heroin, opium, morphine, oxycodone, and Vicodin), which tend to affect only one kind of cellular receptor, alcohol has been found to affect more than 100 unique receptors in the brain. It activates the entire neurotransmitter reward system.

The neurochemical effects of alcohol cause a range of short-term effects—from a mild buzz to slow reaction times, which make drunk driving so dangerous. In the long term, these effects are also the basis for two of the defining characteristics of alcoholism:
tolerance
and
dependence
.

Tolerance to alcohol is one aspect of alcoholism that leads to overdrinking. Tolerance can be acute, in one bout of drinking, or long-term, requiring an ever-larger dose to get the same effect over time.

The effect of acute tolerance is a common experience for anyone who has had more than a few drinks. Initially, the first drink has a relaxing effect, but as a person continues drinking, it takes more and more alcohol to produce the same effect. Some people have more acute tolerance than others due to genetic factors. These are the people who can drink everyone else under the table, and they also may be at increased risk of developing dependence on alcohol.

Dependence on alcohol is linked to the interaction of alcohol with the brain's stress system, which alcohol activates. The major component of the brain's stress system is corticotropin-releasing factor (CRF) in the amygdala and related areas, which activates sympathetic and behavioral responses to stress. In a normal stress
response, CRF recruits other parts of the brain to help adapt the mind and body to deal with the physical and mental stressors that challenge it. Alcohol interacts in such a way as to acutely reduce CRF levels in the brain; chronic alcoholism does the opposite.

Research indicates that individuals who are at increased risk of becoming alcoholics are likely to have a genetic makeup causing them to have higher CRF levels than normal. They may be drinking to tame a hyperactive CRF stress system in the brain.

Unfortunately, CRF and the stress system adjust to the alcohol. In the absence of alcohol, the alcoholic feels ill because his or her body cannot easily reverse the high levels of CRF and low reward neurotransmission. This ill feeling may contribute to the tendency of the alcoholic to overdrink—a danger because of the toxic effect on the brain and body of subjecting oneself to so much alcohol.

Sadly, the brain often does not perceive the consequences of the short-term relief that the alcohol brings. When a person overdrinks, she feels good while she is boozing. However, this short-term relief makes the whole system worse off.

Not Either/Or, but Both

During the last century, a debate raged in academic circles whether addiction was a psychological disorder or a physiological disease. Was it a behavioral problem that arises because of environmental factors in early childhood—the nurture argument? Or was addiction a hereditary disease—the nature argument?

We now know it's both. Addiction is a disease with a strong genetic component that also includes aspects of behaviors, cognitions, emotions, and interactions with others, including the addict's ability to relate to members of her family, to members of her community, to her own psychological state, and to things that transcend her daily experience.

Behavioral manifestations and complications of addiction, primarily due to impaired control, can include the following:

• Excessive use and/or engagement in addictive behaviors at higher frequencies and/or quantities than the person intended, often associated with a persistent desire for and unsuccessful attempts at behavioral control.

• Excessive time lost in substance use or recovering from the effects of substance use and/or engagement in addictive behaviors, with significant adverse impact on social and occupational functioning (for example, the development of interpersonal relationship problems or the neglect of responsibilities at home, school, or work).

• Continued use and/or engagement in addictive behaviors, despite the presence of persistent or recurrent physical or psychological problems that may have been caused or exacerbated by substance use and/or related addictive behaviors.

• A narrowing of the behavioral repertoire focusing on rewards that are part of the addiction and an apparent lack of ability and/or readiness to take consistent action toward change, despite recognition of problems.

Over time, repeated experiences with substance use or addictive behaviors damage the brain's reward circuit activity and are no longer as subjectively rewarding. Once a person experiences withdrawal from drug use or comparable behaviors, there is an anxious, agitated, and unstable emotional experience related to suboptimal reward and the recruitment of brain and hormonal stress systems, which is associated with withdrawal from virtually all pharmacological classes of addictive drugs.

While tolerance develops to the high, tolerance does not develop to the emotional low associated with the cycle of intoxication and withdrawal. Thus, in addiction, people repeatedly attempt to create a high. But what they mostly experience is a deeper and deeper low. While anyone may
want
to get high, those with addiction feel a
need
to use the addictive substance or engage in the addictive behavior to try to resolve their uncomfortable emotional state or their physiological symptoms of withdrawal. People with addiction compulsively use even though it may not make them feel good.

It is important to appreciate that addiction is not solely—and mostly isn't—a function of choice. Addiction is not a desired condition. Remember what Joanne told us earlier in the chapter? She wanted to stop. She was aware that she should stop. She had every incentive to stop for the sake of her family and her career. But she could not stop—at least not until she was successfully treated. Simply put, people may choose to get high or drunk but no one chooses to be a junkie or an alcoholic.