Teen Drinking and the Brain

The adolescent brain undergoes profound developmental changes that can be significantly affected by alcohol, which can cause short and long-term developmental deficiencies.

Teenage alcohol consumption in the U.S. is incredibly prevalent. According to the Centers for Disease Control, 11%of alcohol that is consumed in the United States is consumed by people aged 12–20, with 119,000 underage alcohol-related visits to emergency departments. This is particularly concerning because of the developmental state of the teenage brain, which is incredibly susceptible to alcohol-induced changes in structure and function. Consequently, short and long-term physical and psychological development may be profoundly stunted. 

In a recent survey, we asked 2,136 American adults about their alcohol use, reasons for drinking, alcohol-related outcomes, health and more.

Among those surveyed:

• 10.1% had their first alcoholic drink at 11 years old or younger
• 37.5% had their first alcoholic drink between 12–17 years old
• 39.7% had their first alcoholic drink between 18–25 years old
• 12.6% had their first alcoholic drink at 26 years old or older

Effects of Alcohol on Teenage Brain Development

Alcohol consumption during adolescence has several structural and functional consequences that persist throughout adulthood. The time of onset of alcohol use, the frequency of use and the amount used all affect development. Chronic, heavy alcohol consumption from an early age is linked to severe long-term cognitive deficits.  

Short-Term Effects of Alcohol on the Teenage Brain

The precise mechanisms of alcohol-induced alterations in brain development remain unclear, but studies have identified a number of short-term consequences of alcohol use. Among the most impactful of these consequences are reductions in white matter and grey matter in areas of the brain that regulate the reward system and executive functions. In addition, the integrity of white matter and synaptic connectivity is reduced in adolescents who use alcohol regularly. 

Alcohol has also been shown to cause neuroinflammation, which is the brain’s attempt to limit the damage caused by alcohol. Neuroinflammation is currently an area of active research, but it is known that the immediate consequences of neuroinflammation include altered local and long-distance signaling in the brain, which can interrupt normal developmental processes. 

Long-Term Effects of Alcohol on the Teenage Brain

The long-term effects of adolescent alcohol use include potentially severe structural impairments in brain regions that are responsible for tasks as varied as emotional regulation, working memory, visuospatial processing, attention and verbal learning. For example, early adolescent alcohol consumption causes acute neuroinflammation and reduced structural integrity in signaling pathways that are important for correct prefrontal cortex development and activity in the future. When development commences in the prefrontal cortex, critical input is missing from regions that were damaged by alcohol. 

The adverse effects are twofold: 

1. Abnormal structural integrity in the prefrontal cortex leads to impairments in cognitive control and emotional regulation
2. Communication between the prefrontal cortex and other parts of the brain (particularly the reward system) is altered, which can negatively impact learning, memory and development of social skills

These effects persist into adulthood and, although data is controversial, there is evidence that suggests that early alcohol-induced damage is irreversible. The presence of neuroinflammation in the developing brain is also consequential and is linked to neurodegeneration and reduced neuroplasticity. These deficits can have profound and long-lasting ramifications for every aspect of adult life, ranging from inappropriate behavior in social interactions to early-onset dementia and other health problems. Finally, chronic alcohol consumption during adolescence is closely associated with the development of alcohol use disorders later in life.

How Teenage Drinking Impacts Adolescent Brain Behaviors

Alcohol notoriously reduces inhibition and promotes risky behavior. Teenagers are already prone to impulsivity and irrational behavior due to underdeveloped brain regions that regulate behavior. When they consume alcohol, they frequently display dangerous levels of impulsivity and risk and novelty-seeking behaviors. 

Teen Decision Making

Because teenagers are inherently predisposed toward impulsivity and a willingness to engage in risky behavior, they are particularly disadvantaged when they consume alcohol. Reports of teenagers taking extremely ill-advised risks under the influence of alcohol are, unfortunately, an everyday occurrence. Examples of alcohol-fueled risky behaviors include driving under the influence, partaking in unsafe sex and participating in extreme acts of daring.

Teen Personality

Alcohol affects personality by reducing inhibitions and encouraging extroversion. The terms “happy drunk” or “angry drunk” are well known, and they apply to teenagers as well. Notably, alcohol is often cited as the cause of erratic or violent behavior, which can lead to a visit to the emergency room or the local jail.

Teen Memory

Alcohol negatively affects short-term and long-term memory. “Blackouts” may involve partial or no memories of being drunk. Heavy drinking causes significant changes in neurotransmission, and one theory of alcohol-associated memory loss involves an inability for neurotransmitters to interact with parts of the brain that form memories. Critical developmental cues may be interrupted or lost with regular alcohol consumption during adolescence, which can cause permanent damage to brain regions that are responsible for recalling past memories and creating new memories. In addition, alcohol affects sleep and the REM cycle, which is thought to be important for memory consolidation and retention.

Teen Learning

Teenage alcohol use is associated with deficits in verbal learning and attention, which have negative impacts on overall learning ability. In addition, teenage drinking has been shown to cause deficiencies in mathematical skills and problem-solving. Associative learning is also affected, likely as a result of the loss of fidelity among signaling pathways that receive, interpret, and process content and contextual cues.

Mounting data indicates that even moderate alcohol consumption during adolescence can have lifelong ramifications. If your teen is drinking, we can help. Call The Recovery Village to find out how our experts can help you address your teen’s alcohol use.

Editor – Megan Hull

Megan Hull is a content specialist who edits, writes and ideates content to help people find recovery. Read more

Medically Reviewed By – Dr. Annie Tye, PhD

Annie earned her PhD in Neuroscience from the University of Iowa, where she studied migraine pathophysiology. Read more