What Is Addiction?

Addiction is a chronic, relapsing disorder of the brain that leads a person to compulsively seek out a substance despite experiencing negative consequences.

Even if the consequences are serious and disruptive, brain changes caused by addiction make it extremely difficult for a person to make healthy choices and stop using their substance of choice. Brain pathways that are affected by chronic substance misuse include those responsible for reward processing, stress management, and self-control.

The Disease Model Of Addiction

Professionals who study and treat addiction now understand it as a disease because of the measurable functional and physiological changes that chronic drug use can cause. Like other chronic diseases, addiction causes a disruption in the ability of a specific organ to function, has serious harmful effects, and is both preventable and treatable.

However, even when treated, a person is still considered to have the condition because when they stop managing their chronic disease, they may experience a relapse. Untreated chronic diseases, such as addiction, can last a lifetime.

How Substance Use Changes The Brain

Drugs and alcohol work in the brain by interfering with the way brain cells (neurons) communicate with each other. Certain substances may activate neurons because their structure mimics that of a naturally occurring neurotransmitter,  while others may cause neurons to release exceedingly more natural neurotransmitters than usual or prevent the “clean up” from previous neurotransmitter releases. This results in stronger signals to either induce or prevent certain brain activities, depending on the type of drug.

As a person continues to use drugs or alcohol regularly, the brain adapts to the presence of the drug. It reduces the amount of natural neurotransmitters it produces in order to function “normally” while under the influence of a substance, which is called physical dependence. With these adaptations, a person often develops tolerance. Having a tolerance to a drug means that it requires increasingly more of a substance to produce the same effects or taking the same dose no longer achieves the desired effects.

Sometimes, the brain adaptations that occur with physical dependence result in withdrawal symptoms when the substance is no longer present. Withdrawal symptoms may range from mild physical or mental discomfort to life-threatening symptoms, depending on the substance.

Parts Of The Brain Affected By Substance Use

Substance use heavily affects three main areas of the brain. Certain substances may have effects on other parts of the brain and body, but consistent brain changes are usually seen in the following areas with chronic substance use.

The Basal Ganglia

This area of the brain plays a large role in modulating pleasure from healthy activities such as eating, socializing, and sex. As such, it is known as part of the “reward circuit,” contributing heavily to habit formation and routine. Drug overactivation of this circuit and the resulting brain adaptations make it difficult to feel pleasure from anything besides substance use.

The Extended Amygdala

This area of the brain manages stress and the feelings that result from it. Repeated drug use makes this circuit increasingly sensitive, causing growing amounts of anxiety, irritability, and unease each time the drug influence begins to wear off. Further use can lead to such sensitivity that a person seeks drugs solely to get relief from these discomforts rather than experience the pleasure the substance provides.

The Prefrontal Cortex

This part of the brain is responsible for thinking, planning, problem-solving, decision-making, and self-control. Changes to this area of the brain, combined with the effects on the basal ganglia and amygdala, make it difficult for a person to decide and stick to a decision to quit. This is a particular challenge for teens dealing with substance use because their prefrontal cortex has not finished development.

Changes to these three brain areas drive the compulsive behaviors that define addiction. However, some drugs can also affect the brain stem, which controls the body’s basic life functions. Interference with the brain stem can affect heart rate, breathing, and sleeping, which can easily cause death in the event of an overdose.

Is Substance Use A Choice?

In the vast majority of situations, the initial decision to use substances is a choice. But even with first use, there can be dangerous consequences. If a person continues to drink alcohol or take drugs, changes may occur in the brain that interfere with their ability to make healthy decisions or resist intense urges to use the drug. At a certain point, a person will continue seeking and using the substance despite an awareness of harmful, ongoing consequences. This is what characterizes addiction.

Once an addiction develops, a person has very little control over their ability to resist substance-seeking behaviors. Like any chronic disease, they need appropriate treatment to get well and persistent efforts to continue controlling their addiction.

Before addiction develops, a person may be choosing substance use. However, when an addiction develops is different for each person depending on their biology, environment when growing up, current environment, and developmental stage. Some people may never develop an addiction to substance use, while others may develop an addiction from just a few exposures.

Are People With Addiction Responsible For Their Actions?

People with addiction are responsible for their initial decision to misuse their substance, but after that, it becomes difficult to draw a line. Ethical debates on the morality of a person’s actions may take into account the experiences they had growing up that led them to substance misuse, the influence of brain changes, and how much support they have to get help for their addiction.

It is commonly agreed that there should be a balance between accountability and understanding. The professional understanding of substance use disorders (SUDs) recognizes a person’s freedom of will alongside the physical and physiological changes that make it difficult to control their behavior.

Still, it’s important to remember that it’s okay to set boundaries with someone with an addiction. Their actions may, intentionally or unintentionally, hurt those around them, and it can be healthy and necessary for you to create distance or remove them from your life. While it can be a hard decision to make, it might be eye-opening for the person with the addiction and be the push they need to seek treatment.

Addiction treatment can be very effective, and many people with addiction are able to find a path to recovery that allows them to live full and healthy lives.

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Why Do Some People Say Addiction Is Not A Disease?

Addiction is a disease, and people who say otherwise likely have a misunderstanding of addiction. They may believe that substance use continues to be a choice because it was a choice initially. They may not understand the brain changes that occur with chronic substance use. Or, they may need someone to blame for the hurt that they have experienced as a result of a loved one with addiction.

There are many reasons why it may be difficult for someone to accept the disease model of addiction. Support groups, such as Al-Anon, and therapy can help people cope with past or present harm from an addicted loved one’s actions.

Finding Addiction Treatment

If you or a loved one are struggling with addiction, evidence-based treatments are available to help. Contact a treatment provider today and get started on the journey to recovery. A step today can create an addiction-free future for tomorrow.