The Science of Addiction

More than 932,000 individuals have died from drug overdose since 1999, and in 2020, nearly 92,000 deaths due to drug overdose occurred in the U.S., according to the CDC.1 If an individual in Orange County and surrounding areas is seeking information, advice, or help for addiction, it can help to know the science of addiction.

Table of Contents

What is Drug Addiction

Addiction is a chronic, relapsing condition marked by compulsive substance seeking and use despite negative repercussions. It’s considered a type of brain disorder since it involves functional brain circuit changes affecting stress, reward, and self-control. These changes can last long after the individual has stopped using the substance.2

Addiction is similar to other conditions, like heart disease. Both interrupt the healthy, normal functioning of organs in the body, both cause harmful effects, and both, in many cases, are treatable and preventable. If not treated, they can affect a person for a lifetime and may even cause death.

Individuals of all ages struggle with the negative consequences of drug abuse and addiction:

Teenagers who abuse drugs might act out and often perform poorly in school. Some may even drop out entirely. While the brain is still developing, drug use can lead to lasting changes in the brain and put the individual at a higher risk of addiction.3

Adults who abuse drugs may have issues remembering, thinking clearly, and paying attention. They could develop poor social behaviors because of drug abuse, and their relationships and work performance suffer.

Parents’ drug abuse can lead to stress-filled, chaotic homes and child neglect and abuse. Conditions like these harm the development and well-being of kids in the household and can set the stage for next-generation drug use.

Babies exposed to substances in the mother’s womb can be born underweight and premature. This exposure can slow the child’s learning capability and impact their behavior later in life. They can also become dependent on drugs like opioids that the mother uses during pregnancy. This is a condition referred to as neonatal abstinence syndrome (NAS). 4

Why Do People Take Drugs?

Generally, individuals take drugs for several reasons:

1. To Feel the Pleasurable Effects

Drugs produce intensely pleasurable feelings. Depending on the type of drug used, they’ll create an initial euphoria followed by other effects. For instance, with cocaine or other stimulants, they’ll experience the “high,” and then they’ll experience feelings of self-confidence, power, and increased energy. With opioids like heroin, feelings of satisfaction and relaxation follow the initial euphoria.

2. To Help Feel Better

Certain individuals who struggle with stress, depression, and anxiety, begin using drugs so they can feel less anxious. Anxiety and stress often play a huge role in starting and continuing the use of drugs. They also can cause an individual to relapse (go back to using drugs) after they’ve recovered from addiction.

3. To Help Perform Better

Certain individuals feel pressured to improve their performance in sports or improve their focus on their schoolwork. This can often lead them to try and continue using drugs like cocaine or prescription stimulants.

4. Out of Social Pressure and Curiosity

Teenagers are typically more at risk for this one since peer pressure can be extreme. Since teens are still in their developmental period, various risk factors are involved (i.e., peers are using drugs). 

The initial choice to start taking drugs is usually voluntary. However, as the individual continues using, their ability to demonstrate self-control can become compromised and seriously impaired. This self-control impairment is a hallmark of addiction. 

There have been brain imaging studies of individuals with addiction that show physical changes in brain areas that are crucial to:

Changes like these help explain addiction’s compulsive nature.

Why Do Some People Become Addicted to Drugs While Others Don't?

Like with other disorders and conditions, the chances of developing an addiction will differ from one individual to the next. No one factor will determine an individual’s risk of becoming addicted to drugs. Generally, the more risk factors an individual has, the higher the risk of taking drugs that will become regular use and then addiction.

On the other hand, protective factors can help reduce an individual’s risk. Protective factors and risks can be either biological or environmental.

Some examples of risk and protective factors include:

Aggressive behavior in childhood is a risk factor for drug addiction.6 Protective factors would be self-efficacy (belief in self-control).7

Lack of parental supervision is a risk factor for addiction.8 Protective factors would be more parental monitoring and support.8

Drug experimentation is a risk factor.9 Protective factors would be extracurricular activities.10

When individuals first use a drug, they may perceive its effects as positive. They may also think they can control their use. However, drugs can take over an individual’s life quickly.

Over time, if the individual continues using the drug, the individual must take the drug to feel “normal.” Also, other pleasurable activities they use to enjoy become less satisfying.

They have difficulty controlling their urge and need to take the drug despite causing many issues for themselves. Some individuals may begin feeling the need to take the drug more often or take more of the drug to gain the same effect. These types of things are signs of addiction.

Even fairly moderate use of drugs can pose dangers. Take a social drinker as an example. They become intoxicated and make the wrong choice of getting behind the wheel of their car. Now that pleasurable activity of social drinking can turn into a tragedy that can impact many lives if they get into an accident.

Using drugs occasionally, like opioid misuse to get high, can have devastating effects, including overdose and impaired driving.

Biological and Environmental Factors that Increase the Risk of Addiction

There are various biological and environmental factors that can increase a person’s risk of addiction.

Biological Factors

Biological factors that may impact an individual’s risk of addiction include their stage of development, their genes, and even their ethnicity or gender. Scientists suggest that genes and epigenetics account for between 40% to 60% of an individual’s risk of addiction.11 Also, teenagers and individuals with mental conditions have a higher risk of drug abuse and addiction than others.12


People taking anticonvulsants intended to decrease or eliminate seizures may need to avoid alcohol regularly. Alcohol consumption can cause those anticonvulsants to break down, leading to increased seizure risk. Patients who routinely consume alcohol may notice that they do not get the same impact from their medications and that they may no longer have their seizures under control.

Environmental Factors

Environmental factors involve the family, neighborhood, and school. Factors that could increase an individual’s risk include:

Family and Home

The household environment, particularly during childhood, is an essential factor. Older family members and parents who misuse or abuse alcohol or drugs or break laws can increase their kids’ risk of future drug issues.13

School and Peers

Peers and friends can have a powerful influence during the teenage years. Teenagers who use drugs can sway friends and peers to try drugs with or without risk factors. Poor social skills or school struggles can place a child at further risk of abusing or starting a drug addiction.14

Other Factors that Increase the Risk of Addiction

There are other factors to look out for when it comes to a person’s risk of addiction. These include:

Early Use

Anyone of any age who takes drugs can develop an addiction. However, research shows that those who start using drugs early have a higher chance of developing severe issues. This can be due to the harsh effects drugs can have on a developing brain.

It can also result from a combination of early biological and social risk factors. These factors include exposure to sexual or physical abuse, lack of stable family life or home, mental illness, and genes. Even still, the fact remains that the use of drugs early on in life can be a strong indicator of issues ahead, including drug addiction.15

The Way the Drug is Administered

Injecting or smoking a drug increases its potential for addiction. Both injected and smoked drugs get into the brain within seconds. This produces an intense rush of pleasure.

But, this intense high generally fades within minutes. Scientists feel this strong contrast causes individuals to continue using the drug to recapture that intense high.16

How Drugs Work in the Brain

An individual’s brain consists of various parts that have interconnected circuits that work as a team. Specific circuits of the brain are in charge of coordinating and performing certain functions. Groups of neurons send signals back and forth to different parts of the brain, nerves in the body (the peripheral nervous system), and the spinal cord.

To send a message (or signal), a neuron releases a neurotransmitter into the synapse (or gap) between itself and the next cells. Then the neurotransmitter crosses the gap or synapse, attaching to the receptors on the receiving neuron – sort of like a key going into a lock. This leads to changes in the cell that’s receiving. Transporters (other molecules) recycle neurotransmitters (bring them back to the releasing neuron), which limits or shuts off the signal between neurons.

Drugs disrupt how neurons receive, send, and process signals through neurotransmitters.17 Certain drugs, like heroin and marijuana, may activate neurons due to their chemical structure mimicking that of the body’s natural neurotransmitter. This enables the drugs to become attached to the neurons and activate them.

While these drugs mimic the body’s natural chemicals, they do not activate the neurons in the same manner as a natural neurotransmitter does. And they cause irregular messages to be passed on through the network.

Other drugs, like cocaine or amphetamine, can cause neurons to release irregularly significant amounts of natural body neurotransmitters. Or, they can prevent regular brain chemical recycling by disrupting the transporters. This can also disrupt or amplify regular neuron communication.

Parts of the Brain Affected by Drugs

Drugs can change essential areas of the brain that are needed for life-sustaining functions. They can also feed the compulsive drug abuse that characterizes addiction. Areas of the brain that drug abuse impacts include:

This part of the brain plays an essential role in positive types of motivation. Which includes pleasant effects of healthy tasks such as socializing, eating, and sex, and is additionally involved in forming routines and habits. These brain areas create an essential node of what’s sometimes referred to as the “reward circuit” of the brain.

This reward circuit is over-activated by drugs producing euphoria or the “high” many individuals seek. However, the circuit starts to adapt to the drug with repeated exposure. Since the brain adapts, this diminishes its sensitivity and makes it more difficult to feel pleasure from things other than the drug itself.

This area of the brain contributes to stressful feelings like unease, irritability, and anxiety, which characterize withdrawal once the “high” from a drug fades. This motivates the individual to reuse the drug. This circuit becomes very sensitive with the increased use of the drug. Over time, an individual with an addiction will use drugs to experience temporary relief from this discomfort instead of trying to experience the high.

This area of the brain powers the ability to solve problems, plan, think, exert impulse self-control, and make decisions. It’s also the last brain part to mature, which makes teenagers most vulnerable. The shifted balance between this particular circuit and the extended amygdala and basal ganglia circuits makes an individual with an addiction compulsively seek the drug.

Certain drugs, such as opioids, also interrupt other parts of the brain. Such as the brain stem, which controls functions crucial for life, including breathing, heart rate, and sleeping. This interruption helps to explain why overdoses can lead to depressed breathing and death.

Treatment Modalities for Addiction

A comprehensive treatment plan will combine traditional and holistic approaches. This method heals the body and mind and brings balance into an individual’s life.

Comprehensive treatment approaches may combine any of the following (or all):

Addiction recovery isn’t an easy process. Recovering from addiction isn’t an easy process. There are certain steps that need to be taken in a specific order. Essentially, addiction treatment will look something like the following.

1. Drug & Alcohol Detox

Detoxifying oneself from alcohol or drugs is the first step toward recovery. This process typically involves unpleasant withdrawal symptoms and sometimes dangerous consequences, which is why detoxification should be done only under the supervision of a healthcare professional.

Detoxification must be done carefully. Certain drug addictions, such as opioid addiction, are so severe that the individual must slowly taper off their drug usage and use other medications to counter withdrawal symptoms. Detox helps lay down the essential groundwork for long-term recovery when done correctly.

2. Inpatient Addiction Treatment

Following detox, an individual begins their journey to true recovery and rehabilitation from drugs. The most effective rehabilitation program will include inpatient treatment, where the individual stays at an inpatient facility for a minimum of four weeks. Typically this takes place in a relaxing and peaceful residential setting. In this setting the individual will receive a full range of addiction services while staying in an environment free of outside distractions and pressures.

3. Outpatient Addiction Treatment

Outpatient addiction treatment programs generally follow inpatient approaches, but individuals don’t live in a residential facility but at home. They come into the facility typically a few times a week for several hours each day for treatment.

With outpatient services, the individual will usually receive all the fundamental “inpatient” services, except for food, room and board, and certain activities that are only done through inpatient treatment. While it’s not recommended that individuals with addiction skip inpatient treatment, it’s an alternative to the inpatient approach for some people.

4. Aftercare

To help ensure a person’s long-term sobriety and enjoyment in life, aftercare services are provided where individuals can stay connected with a supportive community. They can join in 12-step meetings and share their journey to long-lasting recovery, including any life trials and tribulations.

Addiction is a treatable condition. Scientific research on addiction and its treatments has led to the development of research-based approaches. These tested approaches help individuals stop drug abuse and get back to living productive lives.

Scientists are continually studying drugs’ effects on behavior and the brain. They use the information they get to develop programs that help prevent substance use disorder and support individuals with addiction recovery.

The consequences of drug abuse are varied and vast and impact individuals of all ages. Like with most chronic conditions, like asthma or heart disease, drug addiction treatment isn’t a cure. But individuals in Orange County and surrounding areas can manage their addiction successfully through treatment and regain control of their lives.


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