Physiology Of Alcoholism And Drug Addiction

2024 Author: Harry Day | [email protected]. Last modified: 2023-12-17 15:43

First, briefly about the structure of the brain. The brain is known to be made up of nerve cells (neurons). The cell of each neuron has a long process (axon) on one side of the cell and several short processes (dendrites) on the other side

The neurons of the brain are combined into a neural circuit in the following way: several neurons with their axons connect to the dendrite of the next neuron in the link of the neural circuit, this neuron through its axon is connected to the dendrite of the next neuron, etc. The transmission of information along such a neural circuit occurs as follows: from several neurons through their axons, a nerve impulse is transmitted to the dendrites of the next neurons in the circuit, in this neuron the information is summarized and processed and transmitted through its axon further to the next neuron in the circuit, etc.

There is a small gap (called a synapse gap) between the axon of one neuron and the dendrite of another. Through this gap, a nerve impulse from one neuron to another is transmitted with the help of special substances - neurotransmitters. There are more than 50 varieties of them for different types of signals, but in terms of the formation of alcoholism, one neurotransmitter is interesting, which is responsible for the transmission of the impulse of pleasure - dopamine. In the axon of the 1st neuron (from which the nerve impulse comes) there is a system for the production (synthesis) of dopamine and its storage (depot). On the surface of the dendrite of the 2nd neuron there are receptors that "receive" dopamine molecules coming through the synapse cleft from the 1st neuron.

In this case, the nerve impulse (in this case, "pleasure") passes from one neuron to the next as follows. For convenience, let's say (in reality, of course, this is not the case) that the maximum number of dopamine molecules and receptors that accept them is 10 pieces. Let's assume that there is an impulse of joy along the neural circuit. In this case, the first neuron releases 8 dopamine molecules, they pass through the synapse cleft and fill 8 receptors. The 2nd neuron, by the relative number of filled receptors (80%), determines that an impulse of joy has come and transfers it further. Let us now assume that a calm impulse is going along the neural circuit. The first neuron emits 5 dopamine molecules, they fill 5 receptors of the second neuron, and it registers a calm impulse by 50% filling of the receptors. The same mechanism will be for the nerve impulse transmitting sadness - the first neuron emits 2 dopamine molecules, they fill 20% of the receptors and the impulse of sadness is recorded.

This description is rather primitive and maximally simplified, the real picture, of course, is much more complicated, but the general principle remains the same: the intensity of the nerve impulse transmitted from the 1st neuron to the 2nd is recorded through the amount of neurotransmitter molecules that have entered the receptors.

How does alcohol affect this process (for all drugs this effect is similar, therefore, having understood how alcohol affects, the principle of any drug addiction will be clear)?

Alcohol by its chemical action "squeezes" all dopamine molecules from the depot of the 1st neuron. Getting in large quantities on the receptors of the 2nd neuron, they create an impulse of joy. This is the euphoria that appears with the use of alcohol (or other drugs - they all act in a similar way). With the constant use of alcohol, the body begins to adjust to it and the following changes occur: at the end of the dendrite of the 2nd neuron, the number of receiving receptors increases in order to have time to take in an increased amount of incoming dopamine.

What do these changes lead to in the end?

Let's say that during the development of alcoholism 10 additional receptors were formed. Now, let the person take the previous dose of alcohol, and that "squeezed" the previous 10 molecules of dopamine into the synapse cleft. But the number of receptors in the 2nd neuron is already twice as large. So, now 10 dopamine molecules fill only 50% of the receptors and, accordingly, an impulse of calm is received. This is how the well-known effect of lowering (and eventually disappearing completely) of the euphoria from consumption is formed. So what, if the euphoria has disappeared, then the person will simply stop drinking? No. Because when he is in a state without alcohol, the 1st neuron releases 5 molecules of dopamine (which corresponded to the previous signal of calmness), which already fill 25% of the receptors, which already corresponds to the signal of sadness.

And if before a person in a sober state felt calm and drank for the sake of joy, now in a sober state he feels depressed and drinks for the sake of peace (or rather, relief). If earlier alcohol was a pleasure, now it has become a necessity.

Is the previous number of receptors restored over time?

Over time, additional receptors are gradually "preserved", and the work of the nervous system in a sober state is normalized. Until this happens, a person feels unsatisfactory without alcohol, and this condition is called post-withdrawal syndrome.

The most critical state of post-withdrawal syndrome lasts the first three months of complete abstinence from alcohol (additional receptors have not yet begun to be conserved and the person is going through a period of acute dissatisfaction with a sober life).

Further, the acute state of post-withdrawal syndrome lasts up to a year (there is a slow gradual conservation of the main number of additional dopamine receptors).

After that, after 2-5 years of sobriety, the remaining additional dopamine receptors are completely preserved, and after this period the nervous system fully restores its ability to work normally without alcohol

What happens when you drink alcohol again after a long period of sobriety? Usually, when alcohol enters the bloodstream, a process of rapid (sometimes almost in one booze) de-preservation of all additional receptors occurs, and the nervous system returns almost immediately to the state in which it was before the cessation of use. Uncontrolled use, hangover syndrome and other consequences of alcoholism return immediately with full force.

So, alcoholism (and another type of drug addiction) from a biological point of view is a violation of the system of transmission of nerve impulses by certain neurotransmitters. Is it possible from this point of view to cure alcoholism and drug addiction?

There are two answers to this question - one more common, the other less. The first answer is that alcoholism is incurable, it is only possible to maintain remission (the state of disuse), with a new use all its consequences return.

The other answer is more complicated. Yes, a person who has lost control will never have controlled use.

But is this exactly a disease?

By definition, "a disease is a state of an organism, expressed in a violation of its normal functioning, life expectancy, and its ability to maintain its homeostasis." Is the inability to drink in a controlled manner a disruption to normal functioning? From a biological point of view, alcohol is not a substance necessary for the existence of an organism; moreover, it is simply a poison.

Let us then change the question - is the inability to use poison in a controlled manner a violation of normal life, that is, a disease? Or (so that the severity of the issue is not obscured by social stereotypes about the "normality of drinking alcohol"), we will pose the same question about other types of drug addiction - is it a disruption of normal life, that is, a disease, the inability to use controlled heroin, for example (which, by the way, according to its chemical action is very similar to alcohol)?

In addition, after all, entire nations are born with a genetically determined inability to drink alcohol “normally”, but can they be called alcoholics if they have never drunk and will not drink, and at the same time live normally and also feel normal?

If you take a closer look at the violations of biological processes, then it is more correct to define alcoholism not through the loss of dose control (after all, the inability to drink normally is present in many people, and this does not interfere with their life in any way), but through a violation of the nervous system, in which it is not able to function normally in its absence, because of which a person CANNOT NOT drink. After all, again, there are forms of alcoholism, when a person drinks in a completely controlled manner, but at the same time he cannot not drink at all. Then the cure for alcoholism will not be the restoration of dose control, but the ability of the nervous system to function normally without alcohol. In other words, the cure for alcoholism, from this point of view, will be the restoration of the body's ability to function normally in a sober state. And this is just possible, and without any drugs - just with a time of sobriety.

Then the second answer to the question "is alcoholism curable" sounds like this: alcoholism is curable in terms of the disappearance of the body's need for alcohol over time, but the body's reactivity to alcohol (the ability to drink in a controlled manner) is not restored.

At the same time, one should not forget that in addition to the biological component of alcoholism, there is also a psychological one, because of which a person is psychologically incapable of doing without alcohol with an increase in psychological stress (and in this case, staying sober).

The psychological component, in contrast to the biological one, does not go away with a period of sobriety, and this requires a course of psychotherapy for alcoholism. In this case, the treatment of alcoholism (and other drug addictions), from this complex biopsychological point of view, is the maintenance of absolute sobriety (as a result of which there is a gradual restoration of the nervous system) and the process of psychological recovery.

Then, over time (usually long - up to several years), a person acquires the ability to fully live without alcohol (live with satisfaction a sober life without the desire to return to use), which can be called a cure for alcoholism.