During the teenage years, our brains undergo a major renovation project. Just like the rest of the body, the brain spends adolescence developing for adulthood. When alcohol is introduced into the process it can have both short-term and long-lasting impacts on how the brain functions.
Alcohol’s Effects
Specifically, frequent and/or heavy alcohol use by teens can affect how the brain processes memory, social behavior, decision making, emotions and overall mental health. The most recent data from the 2011 Healthy Kids Colorado Survey, administered to high school students throughout Colorado, found the following differences between high school students who binge drink and those who do not. Binge drinking is considered consuming five or more alcoholic drinks in one sitting for boys, four or more for girls.
Binge drinking high school students were less likely to receive good grades, a measure that could be associated with memory impairment and the ability to learn. The same students were also less likely to participate in extra-curricular activities (social behavior), and more likely to use marijuana or have sex (decision-making). High school students who binge drank were also more likely to experience emotional issues such as feeling sad for an extended period of time, and were more likely to seriously consider suicide compared to teens who did not binge drink.
Marijuana’s Effects
As with alcohol, frequent and/or heavy marijuana use can impact a teen’s behavior, emotions, and decision-making.20
Colorado high school students who reported using marijuana in the past 30 days were more likely to feel sad for extended periods, and seriously consider suicide than students who did not use marijuana. These students were also significantly more likely to engage in high-risk behaviors like binge drinking or having sex. Grades, involvement in extra-curricular activities, and physical activity rates were also lower among students who used marijuana.
Physical Changes to the Brain
Research into alcohol’s physical impact on brain development also reveals alarming results as alcohol can weaken, damage, or even stunt the growth of certain areas of the brain including:
White Matter: This is the brain’s network. Heavy use of alcohol by teens can weaken the brain’s white matter tissue.
Hippocampus: Buried deep within the brain the hippocampus controls memory. Alcohol can begin to affect the hippocampus after one or two drinks. When people have a hard time remembering conversations or activities that happened while they were drinking it is because the hippocampus was being impacted by alcohol. Heavy alcohol use in teens has been shown to physically shrink the hippocampus. This can cause memory and learning problems well into adulthood.
Frontal Lobes: Control emotions. Drinking alcohol for a long period of time can begin to damage the frontal lobes in a teen’s brain. This damage can make it difficult for teens to deal with emotions and urges.
Research has also found that adults who began regularly using marijuana before age 18, and continue to use it, have actually altered how their brains work. Consistent use creates a new level of “normal” brain performance that is lower than what they would have achieved by not using marijuana.20