WHAT IS ADDICTION?
According to the American Society of Addiction Medicine, addiction is a treatable, chronic medical disease that involves complex brain circuits, genetics, the environment one lives in, and an individual’s own life experiences.
When looking at the neurobiology of addiction, it is important to remember that some people who partake in drug use will not develop an addiction. There are several factors that play a role in one’s risk of addiction, including both environmental and genetic components. Those who do go on to develop addiction will begin to engage with substance use that becomes compulsive and will continue to do so despite harmful consequences.
A key component to understanding addiction is knowing how it affects the human brain. The Mesolimbic Dopamine Pathway, or the brain’s reward system, controls the parts of the brain that deal with motivation, pleasure, and behavior reinforcement. Whenever someone partakes in an activity that brings them joy, the brain releases dopamine and will want to repeat the activity. Dopamine is a chemical messenger within the brain that reinforces feelings of reward and satisfaction.
Substance use can cause changes with the prefrontal cortex, which can lead to impaired decision making and poor impulse control. Substances will also affect the Amygdala and Hippocampus, parts of the brain that deal with the emotional and memory-related aspects of addiction. All of these changes create a cycle of craving, withdrawal, and return to use, making addiction difficult to treat.
HOW DO BRAIN FUNCTIONS CONTRIBUTE TO ADDICTION?
When dopamine is released, it is telling our brain that this experience feels good. The Amygdala connects those emotions (whether good or bad) to the experience and the Hippocampus associates the majority of that experience to the experience. Drugs can also damage the prefrontal cortex, which leads to poor impulse control.
All of these factors combined can strengthen the urge to use substances again; as the brain connects feeling good to substance use, resistance becomes more difficult. It is important to note that the prefrontal cortex is the last area of the brain to fully develop, which is why teens and young adults are more vulnerable to substance use.
HOW DOES THE BRAIN RESPOND TO ADDICTIVE SUBSTANCES?
When a person uses substances, the brain will release dopamine at up to 10x the amount compared to activities liking eating food or sexual intercourse. Even when taking the drug is no longer enjoyable, your body will continue to release these high amounts of dopamine, intensifying the desire to use the substance again.
When the brain’s reward pathway is hijacked by addictive substances, enjoying naturally rewarding healthy activities becomes more challenging. This is one of the reasons why people living with addiction may be less likely to enjoy things that once brought them joy.
TREATMENT OPTIONS AND MOVING FORWARD
Addiction can be treated using a multidisciplinary approach. Treatment options include treatment with medication (the gold standard for opioid use disorder), therapy to rebuild areas of the brain damaged by addictive substances, meaningful and supportive human connection and engaging in purposeful activities to strengthen the reward pathway.
Addiction is a chronic condition that negatively affects the structures of the brain’s reward pathway beyond a person’s conscious control. Addiction is a treatable condition, and together, we can move towards a future with reduced stigma and higher access to resources for those living with addiction.
