Addictions are chronic relapsing psychiatric disorders characterized by the compulsive and uncontrolled use of a drug or activity, which usually results in maladaptive and destructive outcomes. Although some addictions may be good for us, too much of anything is bad. This article is going to be looking at the basis of addiction as well as both genetic and environmental causes of addiction and how they correlate.
Three phenomena characterize addiction: craving, binging, and withdrawal. Impulsivity and positive reinforcement often dominate the first stages, driving the motivation for drug seeking, and compulsivity and negative reinforcement dominate the terminal stages. Addictive drugs bring about adaptive changes in gene expression in our brain’s reward regions which induce mechanisms for tolerance and habit formation with craving and more negative affects, such as depression and loss of control, that persist long after consumption ceases. These neuroadaptive changes are key elements which cause relapse and are also why once an individual become addicted, clinical options are only partially effective. But how does it all start?
Both genetic and environmental variables contribute to the initiation of addiction. Addictions are moderately heritable through generations in our families. Studies conducted on families reveal that an individual’s risk tends to be proportional to the degree of genetic relationship to an addicted relative. However, many genes in the human body influence addiction and we will never find just a single genetic change that causes addiction. Like most other diseases, substance use disorder(a.k.a addiction) is a complex trait. It’s influenced by variations in multiple genes, plus factors from the environment. So, every person inherits a unique combination of gene variations and people with substance use disorder can have different underlying genetic causes. Furthermore, people who share certain high-risk gene variations may or may not have the trait. To sum up, while finding the precise genetic cause is tricky, multiple lines of research do show that genes do in fact influence substance use.
Environmental factors also play an important role in addiction. Several studies have revealed that the initiation of addiction from the use of drugs such as nicotine and marijuana start at an early age and are strongly determined by familial, social, and economical factors. When individuals have access to drugs at an early age, they are more likely to become addicted. In addition, human beings have an innate need to bond and connect. When we are happy and healthy, we will bond with the people around us and won’t feel any need for addictive pleasures but when are isolated, traumatized, or in a depressing period of life, we can’t bond with them so we tend go after and bond with the things that we think gives us pleasure and some sense of relief(like drugs).
In conclusion, addiction or substance use disorder, is similar to other complex diseases such as diabetes and cancer in the sense that it is strongly influenced by genetic background but also greatly influenced by lifestyle and individual choices. Drug addiction can be very dangerous because it can disrupt our brain in ways which doctors cannot fix and can lead to relapse, tolerance, and loss of control. There are several genes that play roles in addiction and the passing down of these addictive traits in families but our actions also will impact our addictive habits. Our differences in lifestyle and actions is what leads to genetic variation in the population and this is why we are not guaranteed to be addicted to the same substance that our father or grandfather was.