Addiction, the Brain, and the Damage We May Not See

Addiction is more than a behavior or a failure of willpower, it is a condition that changes the brain and can significantly influence how a person thinks, feels, makes decisions, and behaves. As the Addiction Policy Forum explains, repeated substance use can affect brain systems involved in reward, survival, self-control, and decision-making. As substance use progresses, what may have initially been a voluntary choice can become increasingly difficult to control.

Brain health should be part of the conversation about substance use.

Substances can alter brain structure and function through mechanisms that may include neurotoxicity, neuroinflammation, changes in blood flow, altered neurotransmitter systems, and disruption of neural networks. Research has identified structural and functional abnormalities associated with several substance use disorders, including changes involving systems responsible for inhibition, mood regulation, reward, memory, and decision-making.

Alcohol provides a clear example. Chronic heavy alcohol use can affect areas of the brain responsible for memory, judgment, attention, impulse control, sleep, and decision-making. Some of these changes may improve with sustained recovery, demonstrating the brain's capacity for neuroplasticity, but recovery does not mean that every individual experiences complete restoration.

This raises an important question for prevention, treatment, and Behavioral Threat Assessment and Management (BTAM): What happens when the behavior we are observing is occurring in a brain that has been injured, altered, or impaired?

Brain injury does not always look like a traditional injury. There may be no visible scar, cast, or obvious physical impairment. Yet changes in executive functioning, impulse control, emotional regulation, memory, sleep, judgment, and decision-making can have profound behavioral consequences.

And the relationship can run in both directions. Brain injury may increase vulnerability to problematic substance use, while prolonged or high-risk substance use may further compromise brain health. Research examining traumatic brain injury and risky substance use has identified plausible pathways involving altered neuroplasticity, neuroimmune signaling, and changes in brain networks.

This is why we should begin looking beyond the question of “What is this person doing?” and also ask: “What may be happening in this person's brain?”

For those working in prevention, behavioral health, public health, and BTAM, this distinction matters. Behavior is information, but so is the biology underlying that behavior.

Understanding the intersection of substance use, brain injury, and brain health may help us recognize behavioral changes earlier, identify underlying risk factors, connect individuals to appropriate interventions, and ultimately build a more comprehensive approach to prevention.

-Author: Jordan Garza, Founder of Lifeline Strategies, LLC

Lifeline Strategies specializes in community health, resilience, and evidence-based approaches to improving public safety and well-being.