Why addiction is now thought of as a brain disease?

We’ve known for over 20 years that addiction is a brain disease. People become addicted due to genetic, developmental, and psychosocial factors, but PET scans showed how addictive substances “hijack” the brain. Once addicted, the brain’s reward, motivation, and memory pathways are changed and alcohol or drug abuse becomes obsessive and compulsive. Once addicted we continue to drink and use, despite all the negative consequences.

Addiction is not a choice, nor a question of morals or character, it’s a chronic disease. Diabetes is not cured because you take insulin and change your diet. Your diabetes is managed, but still present. Addiction is the same, a medical condition that responds to appropriate treatment. Relapse rates for addiction are very close to those of other chronic illnesses like diabetes, hypertension, and asthma.

Each definition brings a unique angle to understanding how addiction is a brain disease, yet they all agree on the chronic nature of the disorder and its complex underpinnings involving both biological and experiential factors.

Full Explanations:

American Society of Addiction Medicine (ASAM)
The ASAM definition emphasizes the chronic and medical nature of addiction is a brain disease, suggesting that it is a long-term condition that can, however, be treated. The definition stresses the complexity of factors contributing to addiction, including the biological (brain circuits, genetics), psychological (individual’s life experiences), and social-environmental aspects (the environment). By mentioning that it’s “treatable,” ASAM likely aims to destigmatize addiction, framing it more as a medical condition requiring clinical intervention rather than a moral failing.

United States’ National Institute on Drug Abuse (NIDA)
NIDA takes things a step further by concentrating on the disorder’s relapsing character and the compulsive behaviours connected to substance misuse. The definition explicitly identifies addiction as both a complex brain disorder and a form of mental illness. It goes beyond just the medical model by also acknowledging the psychological aspects, such as the repeated misuse of substances causing the condition. This definition seems to be tailored towards drug addiction and places a strong emphasis on the neurobiological changes resulting from it.

American Psychiatric Association
The American Psychiatric Association concentrates on the psychological symptoms and neurobiological evidence of addiction. It mentions “distorted” thinking and behaviours, framing addiction as a disorder affecting cognition and action. It also brings scientific evidence into the definition by referring to brain imaging studies that show changes in specific brain regions. This provides a more thorough understanding of how addiction impacts numerous cognitive functions and behaviours. These alterations include judgment, decision-making, learning, memory, and behavioural control.

Addiction is a Brain Disease: The Brain’s Reward System

Some people are more susceptible to developing an addiction than others due to a complex interplay between genetics, other medical conditions and environmental factors. However, anyone who abuses alcohol or other drugs repeatedly is at risk of becoming dependent.

This is because repeated substance abuse affects the way the brain’s reward system functions. It also affects motivation and memory causing a person’s internal motivation system to malfunction to the extent that addictive behaviours, like repeated substance use, replace the original motivations that prompt healthy behaviours.

Our brains have evolved over the millennia to enable and motivate us to discover new and healthy things by rewarding us through the release of the ‘pleasure’ neurotransmitter dopamine. This encourages us to remember the behaviour (for example, eating when hungry) and to repeatedly pursue it to repeat the release of dopamine in the brain. Sex gives us pleasure as nature’s way of motivating us to procreate.

A helpful way to think of how addiction is a brain disease is that drugs of abuse ‘hijack’ this reward system. These substances artificially elicit this dopamine response more intensely than natural rewards. To the individual using drugs or alcohol, this flood of dopamine is experienced as the ‘high’. This tricks the brain into thinking that using these substances is a positive thing, motivating a person to use again and again to repeat the experience of a high.

The brain learns to associate the drug or alcohol use with pleasure. But the body usually builds up a tolerance to the specific drug which leads to higher and more frequent drug use to achieve the same high.

Unlike with healthy behaviours, like eating or having sex, where the dopamine response ends once the behaviour has been carried out, with drugs this response continues long after the substance is consumed. This leads to cravings and compulsive and repetitive drug or alcohol use.

Changes in Brain Structure

Addiction is a brain disease because long-term drug abuse leads to structural changes in the brain. To compensate for the raised dopamine levels, the brain reduces the number of dopamine receptors.

Research has found that a reduction in dopamine receptors is linked to a rise in impulsive behaviour including a rapid escalation of drug use.

Another consequence of a reduction in dopamine receptors is that it becomes more difficult for a person to experience pleasure, even in once highly enjoyable activities. This can also prompt an individual to ramp up their drug use in an effort to feel pleasure and escape from depressive feelings.

Long-term drug use also starts to erode grey matter in the brain’s prefrontal cortex. The prefrontal cortex is an area in the brain that plays a key role in executive functioning including cognitive control functions, personality expression, decision making and moderating social behaviour. Dopamine in this area of the brain influences attention and impulse control.

The reduction in grey matter in the prefrontal cortex reduces an individual’s self-control as well as their ability to logically consider the negative consequences of their drug or alcohol abuse. It also leads to a reduction in the ability of the prefrontal cortex to regulate the brain’s reward system.

Even short-term substance abuse can affect brain structure, especially in young people. Research shows that adolescence is an important time for brain development and adolescents who binge drink risk disrupting this growth with long-term consequences.

Both grey matter volume and grey matter thickness appear to decrease in young people who binge drink. This reduction in grey matter can diminish the brain’s response to risky decision-making, which could lead to greater impulsivity and further risk-taking.

Why do some people become addicted and others do not?

According to the Global Commission on Drug Policy 2017, in 2016 an estimated quarter of a billion people aged between 15 and 64 years – about 5% of the global adult population – used an illegal drug. However, only about 11% of these people were considered to be problematic users or suffer from an addiction.

Moreover, about 10% of recreational marijuana users become addicted to the drug. Similarly, about one in 10 people who misuse prescription opioids become addicted to them.

Experts don’t fully understand why some people who abuse substances begin to use more, and more often, eventually progressing to develop an addiction while others do not.

It is thought to come down to a complex interplay between genetics, environmental factors, past experiences and mental health.

Abusing substances in childhood or adolescence makes a person more susceptible to developing an addiction because the brain is not yet fully developed at this life stage.

Are structural changes in the brain permanent?

The structural changes in the brain of those with an addiction persist long after a person stops using drugs or alcohol which cause cravings as well as put an individual at risk for relapse.

Some changes are permanent while others may not be. The exact nature of the permanence of these brain changes is still unknown.

According to NIDA some brain damage to the dopamine-based reward system appears to be, at least partly, reversable after some months of abstinence.

The brain is considered a resilient organ that is able to heal and grow over time – in line with a concept known as neuroplasticity. This gives hope to many addicts and alcoholics as they begin the process of recovery.

The longer a person remains abstinent the more time the brain has to heal and the less likely they are to return to drugs and the cycle of addiction.

Why it’s important to call addiction a disease

It is important to see addiction as a brain disease and a public health problem so that people receive much-needed treatment instead of counter-productive punishment.

Jail time does not help people but quality addiction rehabilitative treatment does.

Thinking about addiction as a disease, and not as a behavioural choice, reduces the stigma surrounding the condition. It has encouraged countless people to seek help in the form of treatment who would have otherwise kept their drug use a secret, believing they were morally deficient instead of simply sick.

This disease model does not absolve people from taking responsibility for their behaviour. Recovery is hard work and, once an addict or alcoholic gets help and manages to quit, they need to make a choice to stay clean every day. But they must know that once they start using, they will be unable to stop on their own and that that is not their fault.

We’ve provided a simple yet in-depth look at how addiction develops in the brain. We’ve explained why chemical dependency is a brain disease, not a choice, and how this is likely to affect relapse and recovery.

There is always hope and help available. Changes Addiction Rehab Johannesburg is here to guide and support you through each step.

Call 081-444-7000 or email [email protected] to get the help you need today.