Understanding addiction is paramount to addressing its challenges. At The Drug Rehab Referral Service, we’re here to provide answers to your burning questions about the science of addiction, and what exactly happens in your brain when drugs are involved.

1. How Do Drugs Interact with Your Brain?

Drugs have a profound impact on your brain’s functioning, specifically by interfering with the way neurons transmit, receive, and process signals through neurotransmitters. Some drugs, like marijuana and heroin, have chemical structures that mimic natural neurotransmitters in your body. They attach to and activate neurons, although not in the same way as natural neurotransmitters, leading to abnormal messages being sent within your brain’s network.

Others, such as amphetamine or cocaine, can prompt neurons to release unusually large amounts of natural neurotransmitters or disrupt their normal recycling through transporters. This interference amplifies or disturbs the standard communication between neurons.

2. Which Parts of Your Brain Are Affected by Drug Use?

Drug use can impact vital brain regions essential for life-sustaining functions, often driving compulsive drug use that characterizes addiction. The key brain areas influenced by drug use include:

  • Basal Ganglia: Responsible for positive motivation, the basal ganglia plays a vital role in pleasurable effects derived from healthy activities like eating, socializing, and sex. Drugs overstimulate this circuit, resulting in the euphoria associated with a drug high. Over time, the circuit adapts to the drug’s presence, making it challenging to find pleasure in anything besides the drug itself.
  • Extended Amygdala: Involved in feelings of anxiety, irritability, and unease, particularly during withdrawal after a drug’s effects wear off. With increased drug use, this circuit becomes more sensitive, driving individuals to seek the drug for temporary relief from discomfort.
  • Prefrontal Cortex: Responsible for thinking, planning, problem-solving, decision-making, and impulse control. This part of the brain is the last to mature, making teenagers especially vulnerable. Imbalances between this circuit and those of the basal ganglia and extended amygdala lead to compulsive drug-seeking behavior and reduced impulse control in individuals with substance use disorders.

Additionally, drugs like opioids can disrupt other brain regions, such as the brain stem, governing fundamental functions like heart rate, breathing, and sleep. This interference explains why overdoses can result in depressed breathing and, in severe cases, death.

3. How Do Drugs Create Pleasure in the Brain?

The exact mechanism behind the pleasure or euphoria produced by drugs remains a topic of ongoing research. However, it likely involves surges of chemical signaling compounds, including the body’s natural opioids (endorphins) and other neurotransmitters in regions of the basal ganglia, known as the reward circuit. Some drugs cause significant surges in these neurotransmitters, surpassing the smaller bursts associated with natural rewards such as eating, hearing music, engaging in creative pursuits, or social interactions.

Previously, it was believed that dopamine surges induced by drugs directly led to euphoria. However, current scientific understanding suggests that dopamine plays a more substantial role in reinforcing pleasurable activities, encouraging repetition.

4. How Does Dopamine Reinforce Drug Use?

Pleasurable experiences trigger the release of dopamine in the brain, identifying and reinforcing beneficial behaviors like eating or socializing. Dopamine motivates our brains to increase the likelihood of repeating enjoyable activities. When the reward circuit is activated by a pleasurable experience, dopamine signals the importance of that experience, leading to neural changes that promote habit formation.

Drugs can induce significantly larger dopamine surges, powerfully reinforcing the connection between drug consumption, pleasure, and associated cues. These cues can trigger uncontrollable cravings, even when the drug itself isn’t available. This learned “reflex” can persist for extended periods, even in individuals who haven’t used drugs in many years.

5. Why Are Drugs More Addictive Than Natural Rewards?

The brain perceives a substantial distinction between drug-induced rewards and natural ones, akin to the difference between a whisper and a shout. When drugs are misused, the brain adapts by either producing fewer neurotransmitters in the reward circuit or reducing the number of receptors capable of receiving signals. Consequently, the capacity to derive pleasure from natural, rewarding activities diminishes.

This leads to individuals with substance use disorders feeling flat, unmotivated, lifeless, or depressed, making it challenging to enjoy previously pleasurable activities. To counteract this, they often seek drugs to attain a baseline level of reward, exacerbating the problem in a vicious cycle. Additionally, drug tolerance can develop, necessitating higher doses for the same effect.

Understanding the science of addiction empowers individuals and families to make informed decisions and seek appropriate support. At The Drug Rehab Referral Service, we’re dedicated to offering insights and resources to guide you and your loved ones toward a healthier, addiction-free future.