Biology of Addiction

There are a variety of different factors that may increase an individual’s likelihood of developing an addiction. Some of these influencers may be social, environmental, and societal factors, while others may be genetic, hereditary, and biological factors. This article will be focusing on the biology of addiction and what biology has to do with a person’s risk of developing an addiction.

Biological factors can include “anything which affects the function and behavior of a living organism. Internally, this factor can be a physical, physiological, chemical, neurological, or genetic condition which causes a psychological effect.” Every user is different and has a unique situation, but the combination of these factors can create the perfect storm of forming an addiction. According to the National Institute on Drug Abuse (NIDA), biological factors can significantly contribute to an individual’s risk of forming an addiction later in life:

“Scientists estimate that genetic factors account for between 40 and 60 percent of a person’s vulnerability to addiction; this includes the effects of environmental factors on the function and expression of a person’s genes. A person’s stage of development and other medical conditions they may have are also factors. Adolescents and people with mental disorders are at greater risk of drug abuse and addiction than the general population” (NIDA).

An individual’s gender, mental health disorders, ethnicity, and other biological factors can determine a person’s risk for developing an addiction. Since there are many negative stereotypes associated with substance abusers, it is important to be aware that drug addiction is not always a choice; it can develop as a result of factors the person cannot control. Making the biology of addiction known can help an individual achieve long-term sobriety when looking towards the treatment process.

Genetics and The Biology of Addiction

Why do some people experience stronger reactions to a drug than others? Why does one person experience terrible withdrawal symptoms from coming off of a drug but another person does not? These questions may be answered depending on the individual’s genetic makeup. Even though an individual’s genetic makeup may not be the sole reason they develop an addiction, it can definitely make them more vulnerable and susceptible to biological addiction.

When determining the effect that a family has on the individual’s risk of developing an addiction, it can be difficult to distinguish between hereditary factors and environmental factors. The University of Utah Genetic Science Learning Center stated that, “Researchers often study large families to learn which genes may be making them susceptible to addiction. They begin by comparing DNA sequences of family members who are affected by addiction with those who are not, and they look for pieces of DNA that are shared among affected individuals and less common in the unaffected.” From their research, addiction is influenced by genetics.

The Three Phases of Addiction

Biology influences the formation of an addiction in three phases: 1) binge and intoxication, 2) withdrawal and negative affect, 3) preoccupation and craving. Since drugs change the structure of the brain, each of these stages result from changes to the brain’s systems and may take many years to reverse.

1) Binge and Intoxication — Drugs activate the brain’s reward system by releasing dopamine, a neurotransmitter that transmits signals between the brain cells, which is what gives users the pleasurable experience. Over time, it takes more and more of the drug to achieve the same level of pleasure (also known as building a tolerance). As this process happens and the individual begins consuming more of the drug over time, more changes occur to the brain’s systems as a result. This negatively affects how the individual’s brain works.

2) Withdrawal and Negative Affect — Once the user has increased their tolerance and has been consuming larger quantities of the drug, their body won’t be able to function properly in absence of the drug. The drug’s presence in the body will have become the new normal for that person, and they experience harsh withdrawal symptoms without it. Anxiety, restlessness, shaking, and a variety of other withdrawal symptoms may become present when the user tries to stop using the drug.

3) Preoccupation and Craving — With repeated drug use, the individual’s body starts to require the drug in order to avoid withdrawal symptoms. The person may resort to lying, sneaking, or stealing in order to satisfy their powerful drug cravings, and their brain function is seriously affected at this point. Their reasoning, thinking, and decision making skills are significantly impaired and contributes to the cycle of addiction. The drugs have taken a toll on the person’s brain functioning and overall lifestyle, and this may take years to overcome.

There are four circuits in the brain that are involved in addiction:

  • The reward system (located in the nucleus accumbens and ventral pallidum)
  • The motivation and drive center (located in the orbitofrontal cortex and subcallosal cortex)
  • The memory and learning region (located in the amygdala and hippocampus)
  • The control (located in the prefrontal cortex and anterior cingulate gyrus)

Depending on which area of the brain you are focusing on, different parts correspond with different outcomes for the individual. For example, the reward system is responsible for drug cravings.

Biology of Addiction From Generation to Generation

An article from WV Public Broadcasting shares the story of a recovering addict named Brooke and her experience with addiction in her family. “When I was 15, I had my wisdom teeth pulled out, and this was right before the beginning of the oxycontin epidemic, so they gave me oxycontin. And it was just a sensation I can’t explain – it changed something in my mind. And after that it was kind of a slow process for year or two and then it was full-blown. I had to have it,” said Brooke.

 Brooke’s mom, Martha, explained how addiction in her family has impacted her life. “I was dealing with losing my daughter to addiction and then I lost her father – he had an overdose. So I was struggling to get through that and I started drinking. And it made me feel better in the beginning, but you know relationships, family relationships, all the dynamics changed because of the drinking. And I was aware that it was happening, but on the other hand it just made me feel better.

Brooke, her mom, and her dad all had experiences with addiction. WV Public Broadcasting then interviewed Laura Jean Bierut from the Washington University School of Medicine for this article to speak about why addiction is clustering in families. “And so the question is, why is it clustering in families? Is it the environment of the families, or is it the biology of families, the genetic predisposition?

So we really do need to be looking at families when we are treating addiction and to know if there is multi-generational biology of addiction in that family to really try and get everyone in that family into treatment and to encourage abstinence among all family members,” said Bierut.

If you or a loved one is suffering from addiction, or you would like more information on the biology of addiction, call Stop Your Addiction as soon as possible. We will help you to find the resources and help you need for your unique situation. Call Stop Your Addiction today to get started on your journey to long-term recovery and sobriety!

Don’t delay another second
when help is so close.

Call 866-493-0802 Now!


No comments yet! Start the conversation.

Leave a Comment!