Addiction

When we hear the word addiction, drugs such as alcohol, heroin and cocaine often come to mind, but other substances like nicotine, marijuana, and prescription pain medications can also be addictive. Behaviors such as gambling, video gaming, sex and spending can also be addictive and these are called process addictions.

Addiction involves craving, and a loss of control with the substance use or activity continuing, even if it causes harm. This can include problems with relationships, jobs, school, money, or your health.

What Causes Addiction

Addiction has been described as a global humanitarian crisis. It affects millions of people around the world and has been the subject of numerous media depictions. Addiction is potentially one of the most stigmatized conditions there is.

Addiction is not due to weakness or a lack of willpower. Instead, it involves changes in the brain where billions of nerve cells (neurons) communicate through a series of signals and chemical messengers. Where messages leave one neuron, they attach to a receptor on the receiving point¹1.G. Jackson, American Psycholigical Association, American Psycholigical Association.; Retrieved September 21, 2022, from https://www.apa.org/monitor/mar05/dopamine, like a key fitting into a lock.

In addiction, this communication process is disrupted. Large amounts of a brain chemical called dopamine are released, overwhelming receptors and resulting in the ‘high’ that people experience. To keep the feeling going, they take the drug or engage in the behavior repeatedly.

Eventually, the brain changes and adapts²2.A. B. CEO Worlds Best Rehab Magazine, Science of Addiction | What is the Actual Science of Addiction?, Worlds Best Rehab.; Retrieved September 21, 2022, from https://www.worldsbest.rehab/science-of-addiction/, driving them to seek out more just to get the same feeling which is called ‘tolerance’. When tolerance increases or decreases its easy to take too much of a substance or a combination of substances. This overwhelms the brain and stops it sending signals to the rest of the body. This is what can result in an overdose and serious illness, and often death.

Young People & Addiction

Young people are especially vulnerable to addiction. The impulse control center of their brains, known as the prefrontal cortex³3.S. V. Siddiqui, Neuropsychology of prefrontal cortex – PMC, PubMed Central (PMC).; Retrieved September 21, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2738354/ isn’t fully developed, making them more prone to risky behavior and using substances that can cause lasting harm to their developing brains.

If you think your child might be experimenting with substances, talk to them about it. Parents can help by teaching their kids healthier ways to deal with life stresses. Remember, like any other disease such as diabetes or asthma, addiction can be successfully treated, so if you or someone you know has a problem with addiction, talk to your doctor, a mental health professional or an addiction specialist.

Understanding Addiction

Scientists first began to seriously study addictive behaviors back in the 1930s⁴4.K. Mann, D. Hermann and A. Heinz, ONE HUNDRED YEARS OF ALCOHOLISM: THE TWENTIETH CENTURY | Alcohol and Alcoholism | Oxford Academic, OUP Academic.; Retrieved September 21, 2022, from https://academic.oup.com/alcalc/article/35/1/10/142396?login=false. Before this, it was widely assumed that people with addictions, were in some way morally flawed or lacking the willpower and mental strength to overcome their problems.

Innovative brain imaging techniques have revolutionized our understanding of what is happening to the brains of affected people. We can now see that addiction changes the brain structure in ways that can alter the way it works, and process information to understand the ways that this might impact their choices and behavior.

Addiction Reward & Dopamine

Deep in the brain sits the reward and neuronal pathway that connects clusters of neurons for different areas of the in a highly organized way, also known as the mesolimbic pathway⁵5.C. Helbing, The role of the mesolimbic dopamine system in the formation of blood-oxygen-level dependent responses in the medial prefrontal/anterior cingulate cortex during high-frequency stimulation of the rat perforant pathway – PMC, PubMed Central (PMC).; Retrieved September 21, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5363663/.

The reward pathways primary function is to reinforce sets of behaviors, so if we think back to evolutionary times, it was helpful to have a mechanism that rewards us for behaviors useful for survival, things like finding food or escaping from a source of danger.

The primal reward pathway ‘rewards’ actions we take that help up stay alive so that we can repeat it the next time we’re in a similar situation. The reward pathway achieves all this primarily through the use of a particularly neurotransmitter called dopamine, following an appropriate action.

A small burst of dopamine is released by the reward pathway. This causes you to feel a small jolt of satisfaction, which acts as a reward for keeping yourself alive, encouraging you to repeat the same behavior in the future.

Dopamine signals also act on areas of the brain involved in memory and movement, which help us build up memories of what is good for survival, and makes it easier to do it again.

Dopamine is also released when good things happen to us, rewarding experiences such as winning a game, or getting a compliment at work, send signals to release bursts of dopamine, more indirectly.

If you take a painkiller, like an opioid, or have an alcoholic drink certain neurons within your central nervous system work to suppress the resulting feelings of relaxation with a spike in dopamine. This spike in dopamine paves the way for both drugs and non drug addictions because whenever an action or substances are used, such as excessive gambling, alcohol or drugs, the reward system floods the entire circuit with levels of dopamine, up to 10 times higher than a natural reward, depending on the route of administration⁶6.A. Alcaro, R. Huber and J. Panksepp, Behavioral Functions of the Mesolimbic Dopaminergic System: an Affective Neuroethological Perspective – PMC, PubMed Central (PMC).; Retrieved September 21, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2238694/.

This can happen almost instantaneously, with the effects lasting much longer than a natural stimulus. The over-stimulation of the brain’s natural reward mechanism produces intensely euphoric and pleasurable sensations that act as strongly motivated people to seek out more events.

Understanding Addiction Tolerance

Tolerance occurs when you need to experience more and more of the substance or action in order to release the same amount of dopamine. This explains the predominance seeking behaviors commonly seen in long term addiction, because eventually areas outside of the reward pathways are affected. These other areas include brain regions involved in decision making judgments and even memory, begin to physically change with some areas having neurons added, and some areas dying away⁷7.H. R. Kranzler and T. K. Li, What Is Addiction? – PMC, PubMed Central (PMC).; Retrieved September 21, 2022, from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3860451/.

The overall effect is that drug and alcohol seeking behavior become driven by habits, rather than conscious thoughts, almost like a reflex. In effect, that person’s brain has become hijacked and concentrated on the sole purpose of seeking out more and more of the addictive substance, whatever the cost.

How Does Someone Become an Addict?

Not everyone who tries a drug will become an addict, so why do some people develop strong addictions, while others don’t? We can split the answer into three main reasons; genetics, environment and development.

Many people describe themselves as having an addictive personality⁸8.A. B. CEO Worlds Best Rehab Magazine, Do I Have Addictive Personality Disorder? | Signs of Addictive Personality, Worlds Best Rehab.; Retrieved September 21, 2022, from https://www.worldsbest.rehab/addictive-personality-disorder/. Recent research suggests that up to 75% of the likelihood of developing addiction comes from your genetics, these biological differences can make a person more or less vulnerable to addiction, and can influence the strength of any withdrawal symptoms experienced, if they attempt to quit.

Are You Born with Addiction?

Addiction is a complex trait and is most likely influenced by multiple different genes. No one is born destined to develop an addiction. So what else is at work here?

Social environment plays a significant role in rewiring your reward system. For example, if you’ve got a stable relationship or are doing great at work, you’re going to feel good. It’s thought that people who don’t have much stimulation of their reward pathways through social environments or interactions are more likely to seek out addictive activities as a way to stimulate their own neglected reward pathways.

One study found that monkeys lower down on the social hierarchy, who didn’t receive as many social benefits, such as grooming were much more likely to self administer cocaine in a laboratory than the monkeys higher up in the social ladder⁹9.S. S. Negus, Rapid Assessment of Choice between Cocaine and Food in Rhesus Monkeys: Effects of Environmental Manipulations and Treatment with d-Amphetamine and Flupenthixol – Neuropsychopharmacology, Nature.; Retrieved September 21, 2022, from https://www.nature.com/articles/1300096.

Young People get Addicted Easier

Addiction can happen at any age, but we also know that the earlier in life someone tries drugs, the more likely it is that they will develop an addiction because the brain doesn’t finish developing until your mid 20s.

One area of the brain that continues to mature during adolescence is the prefrontal cortex, which is the part of the brain responsible for reasoning, keeping your emotions under control, and making decisions.

Unfortunately, this means that the adolescent brain is hardwired for taking risks and making poor decisions. This extends to things like trying drugs or continuing to take them, which is why intervention in this group is especially important to prevent lifelong problems. No one chooses how their brain is going to react, and there is no single factor that determines whether a person will become addicted or not, nonetheless, it’s a real problem that millions of people face every day.

Drug Addiction

A drug is defined as any substance that has a physiological effect when ingested. Drugs can therefore range from something as common as aspirin or caffeine to alcohol and all the illicit or hallucinogenic substances that typically come to mind during any discussion of drugs.

In the context of bio-psychology, the phenomenon of drug addiction is of significant interest. What does it mean to get addicted to a drug? How does this happen? And what does the corresponding brain activity look like?

What Happens When You Take Drugs?

Drugs can be ingested orally like a pill, injected into the bloodstream, inhaled into the lungs or absorbed through any of the external mucous membranes of the body. At the far end they can be shot into the ear, in the eye and under the nails.

Once in the body and absorbed into the bloodstream the drug will continue to have its particular effect until it is metabolized by enzymes, which essentially chop them up until they can no longer perform any function.

Physical addiction

Physical addiction can arise with a wide variety of substances. A few common ones are tobacco, alcohol, cocaine, and opiates. With tobacco, there are many compounds that are ingested, and many of these are harmful to one’s health, but the one that causes addiction is nicotine. This acts on nicotinic cholinergic receptors in the brain. These normally respond to acetylcholine. But nicotine is an agonist for these receptors as well. This causes the receptors to open, allowing ions to enter, which eventually results in the release of neurotransmitters like dopamine, which generates a pleasurable sensation.

The brain responds through neuro adaptation, affecting the binding sites for nicotine, which produces withdrawal symptoms, thus establishing tolerance and dependence. Nicotine addiction can arise very quickly, even after just a few weeks of regular use.

In alcoholic beverages, the active agent is ethanol. This interacts with the brain in a variety of ways. In the cerebral cortex behavioral inhibitory centers are depressed, which lowers behavioral inhibition and processing of information slows down, it affects the center of movement and balance in the cerebellum, as well as the medulla, which impact breathing and consciousness.

Long term alcohol exposure causes neurological changes, resulting in tolerance, which then causes excitation of certain neurotransmitter systems, as well as withdrawal symptoms in absence of the drug. Cocaine on the other hand, is a stimulant, meaning it increases neural activity. It acts by inhibiting the re-uptake of dopamine from the synaptic space, thus keeping their levels quite high.

And finally, opiates like heroin and morphine bind to opioid receptors that normally bind to endogenous neurotransmitters like endorphins, so they mimic innate mechanisms of pain reduction, causing euphoria. Heroin is widely regarded as the most addictive substance we are aware of.

A very high percentage of drug users that go through rehabilitation and completely rid themselves of physical dependence will nevertheless relapse and return to the drug, illustrating that the craving for the pleasurable physical properties of the drug is a huge factor with addiction.

How Drug and Alcohol Addiction Affects the Brain

In long term alcohol and drug abuse, the brain physically changes, shrinks and loses its ability to process information. This is because long term alcohol and drug addiction has damaged a part of the brain called the limbic system, which supports a variety of functions including emotion behavior, motivation, and long term memory¹⁰10.B. Dobbs, The limbic system – Queensland Brain Institute – University of Queensland, The limbic system – Queensland Brain Institute – University of Queensland.; Retrieved September 21, 2022, from https://qbi.uq.edu.au/brain/brain-anatomy/limbic-system.

Effects of Addiction on the Limbic System

When someone drinks or takes drugs, the limbic system emits dopamine, the substance that makes us feel good. With prolonged abuse, the brain stops making as much dopamine as it used to. As a result, the brain’s reward system receives very little input, and the person has a hard time experiencing pleasure of any kind. That’s why many drug and alcohol abusers are no longer interested in the things that used to bring them joy.

Effects on the Frontal Lobe

The frontal lobe of the brain also suffers, it shrinks and loses its ability to function properly. This part of the brain regulates decisions, choices and ability to know the difference between right and wrong. When the frontal lobe is not working as it should, you can’t control the impulse to drink or take drugs.

The Amygdala

The amygdala is controlled by the frontal lobe and is the emotional center of the brain. Without proper control from the frontal lobe the amygdala becomes over sensitive to stress. In this state, someone can have extreme mood swings and become trapped in a state of panic and worry. Because of this, many addicts and alcoholics are constantly fearful and rarely feel safe.

Effects of Addiction on the Cellular Structure of the Brain

The cellular structure of the brain is affected by heavy drinking and drug use as well. The grey cells control thinking and feeling, while the white cells provide the connection and communication between the grey cells. They’re like network cables, passing information from one grey cell to another.

Persistent drug and alcohol use kills the white cells in the brain. This severs the communication pathways so that information is not passed along properly. The brain can reroute these communication pathways using the remaining cells, but it requires abstinence and time for this to happen.

Healing the Brain from Addiction

These negative effects that drugs and alcohol have on the brain are frightening. But there’s good news. If someone can stop drinking and taking drugs completely the brain begins to heal, cognitive function and brain shrinkage can be reversed, new pathways in the brain can be forged and a person can return to normal brain function. If someone can learn to live without the drugs or alcohol, there is hope for full physical recovery.

Addiction Treatment

Can addiction be successfully treated?

Yes, addiction is a treatable condition. Research into the science of addiction and the treatment of substance use disorders has resulted in the creation of research-based approaches that assist people in stopping using drugs and resuming productive lives, a state known as recovery.

Is addiction curable?

Treatment for drug addiction, like treatment for other chronic disorders such as heart disease or asthma, is rarely a cure, though addiction can be successfully managed. Treatment allows people to reclaim control of their lives by counteracting addiction’s destructive effects on their brain and behavior.

Is relapse to drug use a sign that treatment has failed?

No. Because addiction is continuous, relapse, or a return to drug use after attempting to stop can be a part of the process for some people. Drug relapse rates are comparable to those for other chronic medical diseases and people are more likely to relapse if they do not adhere to their medical treatment plan.

While relapse is a common part of the recovery process it can be extremely dangerous and even fatal. If a person consumes the same amount of the drug as they did before stopping, they are at risk of overdosing since their bodies are no longer acclimated to their former level of drug exposure.