Cocaine abuse and neuroscience: the harrowing effects on the user’s brain

How does cocaine abuse change the user’s brain?

Cocaine abuse does come at a high price tag when it comes to the possible and probable changes to the user’s brain and also the brain’s reward system. Australians are known for their resilience and can-do-attitude, however no one is exempt from the effects of long-term drug use, including a hardened Australian cocaine addicts. In the 1930’s it was believed that people with addictions were perhaps morally flawed or did not have any willpower. Today we know that these initial beliefs don’t stand much ground and that a much more holistic approach to understanding addiction is needed. The neuroscience of addiction is complex and provides an in-depth insight into how cocaine can alter the normal function of the brain.

By definition cocaine is a strong stimulant that affects the central nervous system by increasing the level of neurotransmitter dopamine in the brain, which are responsible for regulating a person’s pleasure and movement. In other, more simple words, the initial effect on the brain is a build up of dopamine. A build up of dopamine excites the brain’s reward system but the question is at what price?

Cocaine also causes many intermediate-term alternations to normal brain function. Repeated use of the drug can change the amounts of dopamine transporters. There are also changes to the genes, which arise in the limbic system, which is where the majority of cocaine effects are seen. It is also the limbic system which plays a key role in contributing to the path from drug abuse to drug addiction. To fully comprehend why cocaine users find it extremely difficult to kick the habit, it is important to understand what cocaine actually does to the brain’s reward system.

Repeated cocaine abuse causes long-term changes in the brain’s reward system

With repeated use, cocaine can cause physical long-term changes in the brain systems, particularly the brain’s reward system, which may lead to addiction. The brain starts to adapt therefore making the reward pathways blurred and less able to react to natural reinforces to the drug. Over time the brain builds tolerance to cocaine and so more is needed to reach the intended high. An individual often seeks to reach the feeling of euphoria that they felt on their first cocaine high. Users often respond by increasing their dosage but ultimately this just increases the chances of adverse physiological and psychological effects. The user may also become more sensitive, or desensitized as the case may be, to the effects of cocaine use, for example, anxiety, sleep depravation to name but a few.

The National Institute on Drug Abuse explores the science behind repeated exposure to cocaine, drug abuse, addiction and the brain’s reward system. Normally, dopamine is released by neurons in these circuits in response to potential rewards (like the smell of good food, or the taste of a delicious meal) and then recycled back into the cell that released it, thus shutting off the signal between neurons. Cocaine prevents the dopamine from being recycled, causing excessive amounts to build up in the synapse, or junction between neurons. This amplifies the dopamine signal and ultimately disrupts normal brain communication. It is this flood of dopamine that causes cocaine’s characteristic high and contributes to explaining why it is one of the most addictive drugs on the market. One user involved in a study in 1999, had this to say about the high of the psychoactive drug: “It’s like a hurricane blast of pure white pleasure.” Perhaps a deeper look at the neuroscience behind addiction will shed some light.

The neuroscience of addiction explained

Drug addiction research has made some large leaps in the past decades. The molecular sites of action have been identified for cocaine and other major drugs of abuse. Scientists have discovered that the ‘reward system’ is indeed connected to motivation and emotion. We know that the chemical messenger systems are fundamental to the function of addiction. Understanding the human brain is complex at the best of times, understanding the addicted brain is even more complicated. In the Journal of Addiction Science and Clinical Practice they ask some very important questions regarding the neurobiology of cocaine addiction and understanding the addicted brain:

What does chronic cocaine abuse do to the brain to cause addiction?
In clinical terms, how does repeated cocaine exposure make individuals compulsively continue to take the drug even when they know it may cost them their jobs, possessions, loved ones, freedom, and even their lives?
Why do people with every reason and intention to quit for good find it so hard to get away from the drug, and why do they remain vulnerable to relapse after years of abstinence?

There is, however, no simple answers to these often asked questions. What we do know is that cocaine affects brain cells in a variety of ways; some effects are short lived whilst others remain for weeks, months, years or even a lifetime. According to Nestler and his publication of the Molecular basis of long-term plasticity underlying addiction, he highlights the long-term effects of cocaine use and the changes in nerve cell structure. His study is comprehensive but does not confirm why cocaine abusers continue to experience cravings and even relapses months and even years after abstinence. The persistence of those extreme features of addiction expose that cocaine has some sort of long-lasting neuro-biological effects. Extensive cocaine abuse has been found to cause cells to extend and even sprout new sub-shoots making the understanding of this complex issue even harder to digest. What we do know is that we have come a long way in understanding the neuroscience behind addiction in the past few decades, however there is plenty more to discover in terms of how the addicted brain works and the changes it encounters with long-term cocaine abuse.

The neuroscience of addiction and the effects that cocaine use has on the brain are complex. It is highly important that individuals who are experiencing cocaine addiction or cocaine dependency, seek help as soon as possible as the chances of recovery are much higher with early treatment.