Alcoholism significantly alters the way some important parts of the brain operate. A chronic drinker’s ability to quit drinking gets increasingly difficult as the brain and body become used to the presence of alcohol in the body.
When individuals decide to stop drinking, they will suffer withdrawal symptoms as their brain “resets” to its baseline functioning in the absence of alcohol. This implies that the brain is no longer releasing the same levels of dopamine and other neurotransmitter chemicals as it did when drinking heavily. Simultaneously, the brain begins to re-establish the flow of other neurotransmitters that had been slowed by alcohol.
During withdrawal, for example, the brain begins the creation of neurotransmitter chemicals that produce worry and anxiety. While alcohol reduces the synthesis of these neurotransmitters, they are still present and active when one is sober.
The release of these hormones, together with other physical and physiological changes in the absence of alcohol, might cause a person experiencing withdrawal to feel more angry, sad, annoyed, or exhausted than before.
If people go through numerous bouts of withdrawal followed by a return to drinking, their brains become less likely to release pleasure-causing dopamine and other neurotransmitter chemicals even when they are sober. As a result, people who have quit and then resumed drinking several times may find it difficult to inspire themselves to stay clean, increasing the likelihood that they may relapse into drinking once again.
Aside from the effects on the brain, alcohol withdrawal can be fatal. Withdrawal often occurs within 48 hours of a person’s last drink and can cause “flu-like” symptoms such as fatigue, increased perspiration, raised blood pressure and heart rate, and feelings of tension and worry.
As previously stated, in rare situations, alcohol withdrawal can result in a condition known as delirium tremens, in which the person experiencing withdrawal may become extremely confused and even have hallucinations. At the same time, their body temperature may rise dangerously high, putting them at risk of convulsions. Delirium tremens can be lethal if left untreated.
ALCOHOL AND THE DEVELOPING BRAIN
Drinking during pregnancy can have a variety of physical, learning, and behavioral impacts on the developing brain, the most significant of which is fetal alcohol syndrome, a collection of symptoms (FAS). Children with FAS may have different face characteristics (see illustration).
FAS newborns are also much smaller than the average. Their brains may be smaller (i.e., microencephaly). They may also have fewer brain cells (i.e., neurons) or fewer neurons that function properly, which can lead to long–term difficulties with learning and behavior.
GROWING NEW BRAIN CELLS
For many years, scientists assumed that the number of nerve cells in the adult brain was set at birth. If there was brain injury, the best approach to cure it was to strengthen the existing neurons because new ones could not be created.
However, in the 1960s, researchers discovered that new neurons are formed in adults, a process is known as neurogenesis. These new cells develop from stem cells, which may divide continuously, replenish themselves, and give rise to a wide range of cell types.
The discovery of brain stem cells and adult neurogenesis opens up a new way of thinking about the problem of alcohol-related brain alterations and may lead to a better knowledge of how to treat and cure alcoholism.
For example, animal studies reveal that large doses of alcohol inhibit the formation of new brain cells; experts believe that this lack of new growth is what causes the long–term deficiencies identified in important parts of the brain. Understanding how alcohol interacts with brain stem cells and what happens to these cells in alcoholics is the first step toward determining if stem cell treatments are a viable therapeutic option.