Alcoholism has a devastating effect on our society. Nearly 130 million Americans have been exposed to it in the family. Untreated addiction costs the US $400 billion a year. That’s six times the cost of treating heart disease and diabetes, and four times the cost of cancer. It’s no wonder that 40 percent of all traffic deaths are alcohol related. But did you know that more than half of all homicides and domestic violence incidents are alcohol related?
Of all the ways that alcohol affects the world, the most profound is alcohol’s impact on the human brain. Repeated consumption of alcohol causes long-lasting, negative changes in the tiny nerve cells, or neurons, in the brain. To understand exactly how alcohol affects our brain, let’s start at the beginning: the day you were born. At that time, his brain had already grown about 100 billion neurons. Neurons are living, growing cells in a vast, evolving network of electrical activity in the brain. Neurons are not fixed like electrical wiring. Almost all neurons constantly change their function by adapting to bodily demands, sensations, and environmental stimuli.
Each individual neuron in the brain receives new information and communicates with other neurons to make sense of it. The transmission of information, from one neuron to another, occurs at lightning speed. A neuron can send a signal, restart, and send another signal up to 400 times per second. In fact, all the sights, sounds, smells, touches, and other sensations a baby experiences help his brain create new neural connections. In adulthood, the total number of connections between neurons amounts to 100 trillion.
The connections between neurons are dynamic and change over time. New connections are formed and old ones disappear. The “wiring” of the brain is therefore developed and shaped by life experience. Information coming in through your eyes, ears, and other senses is captured, and your neural connections can change in a fraction of a second, forming new ones. These connections continue to grow and evolve well into adult life.
However, alcohol consumption and its physical effects, such as intoxication and sleep, actually disrupt communication between neurons in the brain. Since alcohol is a depressant, it slows down activity in many parts of the brain. Neurons in the affected areas control the muscles, resulting in relaxation and incoordination. Neurons in the affected areas also control speech, making words slurred and increasingly inaccurate. Similarly, affected neurons control autonomic bodily functions, and heart rate and respiration are impaired.
But what happens physiologically inside the brain when we drink alcohol? Why do we feel good so quickly after consumption? Well, the pleasure we feel from alcohol, as well as food and sex, comes from the release of the natural brain chemical dopamine. We depend on our brain’s ability to release dopamine in order to experience the pleasure of basic human needs, such as seeing, smelling or tasting food. That experience, however brief, is stored in the hippocampal section of the brain. The same physiological sensations occur when we are sexually aroused and even when we see or smell an attractive partner. Alcohol, in particular, produces very large and rapid surges of dopamine, and the brain responds by reducing its normal dopamine activity.
When you start to drink, at first the brain is quickly intoxicated. It releases a good amount of dopamine, a natural feel-good chemical, to combat the poison of alcohol. So it’s actually the dopamine that makes you feel good, not the alcohol. Repeated drinking increases the total volume of dopamine released over time. Eventually, the brain compensates by reducing its own natural production to combat the effects of alcohol. So over time, it takes more and more drinks to create the same high. The brain malfunctions when it adjusts to constantly higher levels of dopamine that are artificially produced by alcohol.
The moment you stop drinking, a dopamine vacuum is created and a craving occurs. The brain then creates a debilitating mood to urge you to drink, in order to raise your dopamine level again. The fastest way to get back to your new “normal” is to drink alcohol. Once this brain malfunction occurs, all activities are affected: from feelings and behaviors to decisions and relationships. This explains why those who abuse alcohol are twice as likely to get divorced than those who do not.
Repeated consumption of alcohol causes lasting changes in neurons in the brain. Scientists call this change “neuroadaptation.” This means that the neurons have adapted to drinking, as if it were normal. Let’s say, for example, that you start drinking regularly at 6 pm every night. At first the brain begins to defend itself against this chemical, since it considers alcohol a poison. It warns you of its effect causing intoxication, nausea, hangover and other symptoms. However, as you continue to drink regularly, the brain compensates and allows you to drink more by producing a stronger tolerance. At this point, the neurons adapt to their drinking patterns.
Now, let’s say you suddenly decide you’re not going to drink tonight at 6 pm. The adapted brain, which now believes that alcohol is a normal part of life, will send out various signals to remind you that it is time to drink as the clock approaches 6:00 p.m. These signals come in the form of mild withdrawal symptoms. to severe, such as irritation, agitation, cravings, and urges. In short, you have basically trained your brain to crave alcohol. (Later, you’ll learn how retraining your brain is the clear path to recovery.)
At this point, one is dependent on alcohol, which is rooted in a change in brain chemistry. Advanced technology, such as magnetic resonance imaging (MRI), diffusion tensor imaging (DTI), positron emission tomography (PET), and electrophysiological mapping of the brain, indicate that alcohol addiction is less of a problem than behavior and more a malfunction of the brain caused by repeated poisoning of the brain.
For years, scientists believed that the number of neurons in the adult brain was fixed early in life. If brain damage occurred, new neurons could not be created. Later researchers discovered that new ones are generated in adulthood, a process called “neurogenesis.” New learning occurs, allowing electrical signals to travel along neural pathways more easily. This inherent capacity for change is called “plasticity.”
This ability to grow new neurons and form new connections was demonstrated in experiments such as the one conducted by Drs. Avi Karni and Leslie Ungerleider at the National Institutes of Mental Health. They had the subjects perform a simple finger-tapping exercise and identified the brain areas involved with MRI brain scans. The subjects practiced this motor task daily, gradually becoming faster and more proficient. After four weeks, new brain scans revealed that the region of the brain involved in this task had expanded. This indicated that regular practice and repetition of the task had recruited new nerve cells and changed the original neural connections.
This finding is the basis of a new scientific hypothesis: internal transformation begins with “learning” (new neural input), which gradually replaces our “negative conditioning” (current neural circuitry). The end result is “positive conditioning” (or new neural circuitry) that directs new emotions and behaviors. Therefore, the concept of “rewiring” the brain for lasting change is a very real and distinct probability.
Alcohol addiction involves the same neural pathways as early memory and learning. So the addictive process weakens everything the brain knew before. Effective recovery implies the reversal of this process. This is a dynamic and comprehensive process that involves what scientists call “retraining” of the brain, or neuroplasticity. More information about neuroplasticity and its success can be found on the NIFAR website.
Alcohol addiction is truly progressive. Over time, it usually gets worse, not better. Behavior patterns associated with alcohol abuse cross all social boundaries and affect both sexes, all ethnic groups, and people of all tax brackets. Therefore, new methods to combat this pervasive disorder must be used to help those who suffer from it. In the process, we will relieve the enormous financial strain of untreated addiction on our health care system, which now exceeds $400 billion a year in the United States.