What motivates people is the prospect of reward. Going to work to realize the dream of owning a home. Doing sports to lose weight. This motivation (or, more precisely, the prospect of being successful) is driven by the mesolimbic reward system in the brain. But the mechanisms can also reward self-destructive behavior, such as when people drink too much alcohol. In the pandemic years, social restrictions may have led to problematic consumption, which also left traces in the brain. The addiction memory makes it difficult to get back.
The branched network of the reward system becomes active whenever we expect a reward or give in to a craving, for example eating when we are hungry. The most important messenger is dopamine. It creates anticipation of happiness, motivates action and reaches its peak when we have achieved our goal, satisfied our desire.
Taking a shortcut on the way to the reward
The consumption of alcohol and other drugs is a shortcut to dopamine release. It then also turns out stronger compared to natural happiness enhancers. Amphetamines, for example, release ten times more dopamine than good food. With alcohol or cannabis consumption, it is still twice as much.
But not only dopamine plays a role in drug consumption. Drinking alcohol activates a wide variety of nerve messengers: Alcohol, for example, docks onto so-called GABA receptors, which has a sedative effect. Glutamate receptors are blocked, which has a further depressant effect on the body. Alcohol also stimulates opioid receptors, which release endorphins and provide a good mood.
Drinking more and more, more frequently changes neurobiology permanently. Studies show that more pronounced alcohol consumption can lead to a reduction in dopamine receptors. Alcohol is then less able to dock in the reward system, meaning larger and larger amounts are needed to feel the same effect. This leads to the development of tolerance.
Did the Corona pandemic create more alcoholics?
During the pandemic, the topic of alcohol consumption has repeatedly been the focus of reporting. The fear was that people would reach for the bottle more often in isolation. There are still no reliable figures on whether the corona crisis has led to more alcohol addicts in Germany or elsewhere in Europe. What we can say, however, is that people who drink a lot on social occasions have tended to drink less in lockdowns because they have had no opportunity to go out. Conversely, it has probably been the case that people who were on the wagon before the lockdowns drank alone at home, thus solidifying the dependence.
What counts as risky use is laid down in the ICD-10 of the World Health Organization – and the criteria can be applied clinically to all drugs. A dependence syndrome is present when there is a strong craving and reduction in control, when tolerance development has set in and the body reacts with withdrawal symptoms as soon as the drug is discontinued. In addition: when the consumption is harmful to the person concerned. Physical damage, such as to the liver, can then be well objectified. Social damage includes, for example, the question of whether one’s own behavior is constrained by consumption.
The path to dependence is usually gradual. It can be described as follows: In the beginning, the hedonic effects of alcohol consumption are in the foreground. You drink because it makes you feel good. Gradually – and this is a slower process with alcohol compared to harder drugs – everything revolves around the bottle. Alcohol abusers often don’t have much social contact anymore, and diet can be neglected as well. This essentially results in the reward being obtained primarily through alcohol.
Brain volume is lost
People who drink excessively also lose lifespan. Studies on this, which used brain scans to examine 36,000 people, included participants who abstained from alcohol completely as well as those who drank four or more units of alcohol a day (one unit was defined as about half a glass of beer). Alcohol consumption was found to be associated with a reduction in total brain volume – the more one drank, the more brain volume was lost. Both the gray matter, which consists of nerve cell bodies, and the white matter, which is made up of nerve processes, are affected to the same extent.
For example, when a 31-year-old person goes from one unit of alcohol to two a day (the equivalent of about one glass of wine), he or she exhibits brain changes that are equivalent to two years of aging. Going from two to three units of alcohol a day is like getting three and a half years older.
Addiction memory exists even years after abstinence
Examining the brains of alcoholics for how they respond to visual stimuli reveals that the prefrontal cortex plays an important role in behavioral control as a mediator between emotions and the mind. When a glass of beer is placed in front of an alcohol abuser, a circuit is set in motion: The reward system jumps in because it is announced that alcohol may be available. The prefrontal cortex, which is connected to the reward system, then has to work very hard to prevent the person from reaching for the glass. In psychology, this is called “top-down control.” In alcohol addicts, this control no longer works. They develop a sensitivity to alcohol-related stimuli such as smells. Even after years of abstinence, the addiction memory is present. Confrontation with alcohol-related stimuli can therefore trigger a strong craving and thus also a relapse.
You can’t erase the addiction memory, but you can overlay it with new content. This means that stimulus exposure training is carried out with people who react very strongly to alcohol stimuli. Subjects are exposed to their favorite drink and, with the help of a therapist, they learn not to reach for it. Here, they experience a decrease in their alcohol cravings, even though they do not drink. This works in a similar way to fear exposure training, where, for example, people with an extreme fear of heights are sent up a skyscraper. True to the principle: You have to face the fear in order to overcome it.