Technology has its mighty hand in every field of the world now. And since the basis of technology is science, how could the medical sector not undergo changes? Neuroscience has always been an area of ​​immense complexities and curiosities. Advances in this area have allowed doctors to delve into the brain and even study the smallest changes that occur due to substance intake.

When we talk about addiction as a brain disease, the brain’s reward system plays a very important role.

Physiologically, the limbic system is the reward system of the brain. The mesolimbic and mesocortical (midbrain) pathways have our cognitive control and functions that would be related to both reward and aversion. Reward-related functions are always stronger and more motivating than aversion, so drug-abusing behavior is stronger in addicts. The reward system connects certain structures in such a way that they generate the sensation of pleasure for certain behaviors or stimuli that are given to the body. In everyday life, it is activated by healthy and vital activities, such as eating and socializing. But ‘Drug Abuse’ is another conduct that generates euphoria, which is enjoyed by the mind. And human nature is to repeat those actions that give us some ultimate satisfaction. The limbic system does more than just give a reward response. In order for any behavior to be reinforced, it must first register as pleasing to the mind and body. The limbic system in the brain recognizes our positive and negative emotions, which nicely explains how our body and mind become dependent on any mood-altering psychoactive substance.

However, with recent developments, neurobiology has been able to study how addiction is related to the brain. Researchers and scientists studied the brain’s reaction to different substances and found that drug abuse actually alters the chemical makeup of the brain, which is what causes addiction and called it ‘brain disease’.

Since the brain is located at the epicenter of human activity, it is the starting point of all phenomena that occur. Whatever we feel, experience, or think, everything is first registered by the brain and, in less than nanoseconds, it commands us to act. It communicates through neurons, neurotransmitters, receptors, and transporters. Yes, it’s very complicated and sounds mystical too (especially for people like me who haven’t studied biology after high school)

How do drugs affect the brain?
Psychoactive substances disrupt the communication systems of the brain. They interfere with the way a message is transmitted and sent to its defined destination. As much as many people say that cannabis would not be called a drug, it is a plant, but the reality remains the same, that is, that everything has a certain chemical composition. For example, the chemical structure of heroin and marijuana are like copies of a natural neurotransmitter. Amphetamines mimic catecholamine neurotransmitters and cause general physiological changes that prepare the body for physical activity and the fight-or-flight response. So, the moment the body is intoxicated with a drug that contains amphetamines or its derivatives, it begins to react unnaturally by increasing blood pressure, increasing alertness, and causing insomnia, blood glucose levels. They can easily activate neurons, giving various instructions to the body to react in a different way than a natural neurotransmitter would! Cocaine can make a person delirious because it releases natural neurotransmitters in bulk and blocks the brain’s natural recycling process of neurotransmitters. Amphetamine causes drug tolerance very quickly and quickly too.

The chronic use of addictive drugs causes alterations in the process by which information from a gene is used to synthesize a gene product: RNA or protein. The nigrostriatal pathway is a dopaminergic pathway that plays an extensive and unavoidable role in addiction. It is part of the transcription factor, which is a protein that controls what has to pass all the information from DNA to messenger RNA. Psychoactive substances block many of the neural and behavioral alterations that are going to be carried to the RNA. Disrupted dopamine transmission is the first thing noticed in cases of drug abuse.

These have been many studies done extensively by medical science researchers on addiction. There is a wide range of chemicals that people use to achieve a state of euphoria. But the gist of it all is that they mess with the normal functioning of the brain by altering the natural chemicals that should be there.

How does the reward system work?
Any time a person does something that puts them in a different state of mind for a while, such as reaching the thrust point in a pleasurable sexual activity, treating the taste buds to a new and very different flavor, or earning an excessive amount of money or any other valuable resources that you can use to become really rich, the brain takes it all in the same way. It activates the same gland and releases the same chemical Dopamine, which functions as a neurotransmitter, in all scenarios that seem pleasurable or exciting. Similarly, whenever the body receives an antibody that becomes too exciting for it, such as any drug, chemical, or alcohol, the body releases a certain amount of dopamine or reduces its level. It’s a problematic scenario if there is too much or too little dopamine being released by the brain. Drugs are addictive because they release up to 10 times more dopamine than a natural neurotransmitter! But when the body becomes tolerant to the same drug and its amount, it can even reduce your normal dopamine release!

The brain tells the body to get more and more involved in activities that give it pleasure. This is how drug addiction is a problem.