The Science Behind How Drugs Affect the Brain

How Drugs Affect The Brain | Transcend Recovery Community

While human beings are generally complex in nature, there is a refreshing simplicity to the way we perceive things as pleasurable and uncomfortable. Food, sex, and exercise = good. Boredom, pain, and social exile = bad. Drugs affect the brain by taking that system, and exploiting it, cutting down the full list of what we enjoy doing and replacing it with one powerful high: the drug itself.


A Crash Course In Pleasure

By observing the biology of the brain, we can see exactly how our brains react to certain stimuli, thus determining how we derive pleasure. Foods rich in sugar and fat (thus, high-calorie meals) trigger the release of neurotransmitters, which seek out their respective receptors, triggering a specific kind of emotion. Dopamine and serotonin, two common neurotransmitters related to pleasure and enjoyment, are released when we’re in the middle of enjoying a particularly tasty donut, for example.

Of course, there’s more to it than that. Our brains not only crave calories and reproduction, but they also crave music, cuddling, bright skies, positive social interaction and praise. These are just a few of the ways to get a “natural high”.

The idea here is simple: as a species, our goal is to develop and grow both individually and collectively. We derive pleasure from doing things that ensure our survival, tribal unity, and reproduction. However, this mechanism is also central to why drugs affect the brain, and are so addictive, playing a significant role in how they affect us and change our entire brain chemistry.


How Drugs Affect The Brain

Through the previously-explained reward system, a drug can become immensely addictive. Our brain has developed an affinity towards certain substances and behaviors and has associated them strongly with positive things, such as survivability and genetic reproduction – thus, these things trigger a massive release of pleasure neurotransmitters, such as dopamine. Sex, food, music and entertainment – when we are enjoying ourselves, eating or reproducing, we’re typically at our happiest.

However, there are limits to how much dopamine our body produces and utilizes when we’re indulging in these natural rewards.

Those limits are entirely broken when drugs are involved. Substances such as cocaine and heroin drugs affect the brain with a potency of 200% to over 1000%. They do this by being structurally like dopamine and other neurotransmitters, hijacking them by making it through the blood-brain barrier and attaching to their respective target receptors.

Different drugs affect the brain in their own way. Alcohol, for example, triggers the sedative effect of the GABA synapses. However, it also releases dopamine. Heroin and other opiates bind to the same receptors as the body’s own natural pain-inhibitors, creating both a euphoric effect and numbing discomfort. Cocaine blocks the reuptake of neurotransmitters associated with happiness and excitability, thus increasing and amplifying your energy, confidence and pleasure. Amphetamine cuts the body’s natural breaks on dopaminergic activity, effectively eliminating fatigue.

Drugs affect the brain in their own way, but have two things in common: the ability to hijack and modify an existing process in the brain, and their role in manipulating or releasing dopamine.

Imagine the brain’s receptors as being of a specific size. The stimulation of pleasure comes from having dopamine match the size of the receptor, fitting perfectly. However, drugs flood the receptors, changing the way they work. The dopamine released by natural rewards then no longer cuts it, and the brain no longer responds to certain rewards as it previously might have. Your threshold for pleasure, so to speak, has been blown through the roof. The result is that instead of feeling content with tasty food, great experiences and sexual gratification, your brain begins to crave the drug as a means of experiencing pleasure. That is how a physical addiction begins – by quite literally teaching your brain to rethink what it means to feel good when drugs affect the brain.

Drugs affect the brain in a physical way as well. Methamphetamine, cocaine and heroin all can deal considerable damage to the brain’s tissues, even going so far as to make near-permanent changes to the way your brain processes glucose, its main fuel source. These changes can be reverted more quickly with a healthy lifestyle, but the process can still take years, and in some cases, some damage is inevitably unhealable.

Some people are genetically more prone to this change in brain chemistry than others. Some people experience the full euphoria of a dose of heroin, but don’t develop the change in brain chemistry as rapidly as others. Yet with prolonged drug use, addiction becomes an inevitability.


Explaining Physical Dependency

Drugs hijack the brain’s natural reward system by introducing massive amounts of artificial pleasure, sometimes forcing the brain to rewire itself to accommodate this sudden change. This effectively cuts into natural rewards and their ability to help us manage stress, emotions, and live a normal life, putting our drug of choice on the top spot for stress management and problem coping.

This change is also the beginning of a physical dependency. Once the brain begins to accommodate a drug’s intensity as the new “normal”, it will fight to decrease the effects felt through that drug to further return to a normal level of pleasure. This, called tolerance, often drives addicts to seek out larger and larger dosages to maintain the same feeling of intense pleasure.

Tolerance is followed by withdrawal. After a while, the brain simply ceases to perform certain functions properly without drugs in the system. Withdrawal from alcohol, opiates and stimulants all manifest differently, but share a few symptoms: feverishness, shivers, mood swings and heavy nausea. Withdrawal can be overcome after a period – in some cases, it can take up a month, although this heavily depends on how addicted a person is, how strong their constitution is, and what kind of substance they are addicted to.


How Physical Dependency Can Be Broken

Both withdrawal and tolerance begin to diminish after a certain period of abstinence, although the exact timeframe changes from person to person. Rehab clinics and other treatment centers begin their program with detoxification, a medically-supervised process by which a patient undergoes a natural transition into a drug-free state. After withdrawal has ended, it can take several months to several years for brain damage when drugs affect the brain to revert.

However, drug addiction itself is also behavioral – this means that, after the effects of tolerance and withdrawal have ended, breaking free from an addiction requires an additional psychological approach to treatment. CBT and related therapies, group/community efforts, and a healthy lifestyle consisting of quality food, regular exercise and at least one passionate hobby are all a part of a solid recovery plan. These are all meant to help you normalize pleasure again, and return to a life where you can enjoy living without addictive substances.

Like a steep slope, addiction is a path that is easily stumbled upon, and difficult to escape. But the pain and effort needed to scale it is worth every single step and sober living programs are there to help you do it.