Substance Use and the Adolescent Brain


Written by Logan Yelderman, MA

Adolescents are infamous attention seekers and risk takers. Many adolescents engage in activities and behaviors that garner attention from others and could be potentially harmful or destructive (whether to the body or mind). These risky behaviors provide a rush or an experience of extreme emotion, which adolescents tend to crave because of their developing emotion center of the brain. Interestingly enough, adolescents are also very coordinated. This is due to the fact that the part of their brains that helps to control coordination and physical mobility is developed at a faster rate than many other parts of their brains, enabling teens to accomplish amazing feats (e.g., winning Wimbledon or winning Olympic gold medals). One of the last parts of the brain to develop is the judgment and decision-making center, leading adolescents to engage in more impulsive behavior without thinking of future consequences. 

Unfortunately, these factors in adolescent brain development point toward a very dangerous conclusion. Adolescents seek to achieve emotionally stimulating events, lack the ability to understand the risk and consequences for their decisions, and have the coordination and mobility to accomplish some very dangerous – though sometimes impressive – feats. Although some adolescents prefer to ride bikes on mountainous terrain or do flips off of diving boards, others decide to experiment with substances (alcohol and drugs) and/or engage in delinquent behaviors. 

While adolescent substance use is dangerous in its own right, it can also affect brain functioning and development in major ways:

Cerebellum and Basal Ganglia

  • This part of the brain controls coordination and physical movement. Many substances affect this part of the brain, decreasing adolescents’ ability to move in a coordinated manner or even physically control parts of their body. For example, adolescents who were once able to flip off of a diving board might find it difficult to do so after using some drugs. 

Amygdala

  • This part of the brain regulates emotion. Adolescents who use substances that affect the amygdala might lose the ability to control their emotions and emotion-driven behaviors. Some drugs might increase emotional responses (e.g., anger and aggression) while other drugs might decrease emotional responses (e.g., lack of fear). 

Hippocampus

  • This part of the brain is related to learning and memory. Substance use often impairs the brain’s ability to make and store memories, which leads to the inability to recall information and the inability to encode information into memory. Thus, when adolescents use substances, for example at school, they are less likely to remember the information from class that day. 

Pre-frontal Cortex

  • This part of the brain is related to judgement and decision-making. Basically, this part of the brain allows individuals to engage in self-control, stifle inappropriate impulses, and think through the potential outcomes of their behaviors and decisions. Adolescents who use drugs that affect the pre-frontal cortex have fewer inhibitions. This means that their ability to say no to risky or dangerous situations becomes more difficult. This often leads to adolescents engaging in risky behaviors such as unprotected sex, physical violence, or using other drugs.

Not only do substances temporarily affect these brain structures and adolescents’ decisions and behavior, but substance use can also affect the development of these brain structures. Chronic substance use (continued use and heavy use) can damage or negatively impact the developmental process of the adolescent brain. These effects include reduced brain matter volume, reduced neural activity, and reduced neural connections. This can lead to permanent changes in adolescents’ ability to make and store memories, regulate emotion, engage in highly coordinated behaviors, and control impulses. Further, chronic substance use can lead to co-occurring disorders and mental health issues related to brain development and function. Intervening before adolescent substance use becomes a chronic issue or a disorder can be critical in the trajectory of adolescents’ lives and the development of their brains. Juvenile drug courts provide resources and treatment for those in the juvenile justice system who struggle with substance abuse issues. 

For more information about how juvenile drug courts can address adolescent substance use, see the National Council of Juvenile and Family Court Judges’ work on juvenile drug courts.