When Does the Brain Reach Maturity? It’s Later than You Think

Life is full of milestones. Many are based on age: getting your driver’s license at 16, voting for the first time at 18, and being able to purchase alcohol at 21. With all these big events, you may think that your teen or twenty-something is officially a grown-up and ready for anything. Their brain, however, isn’t.

Dr. Angeline Stanislaus is the Chief Medical Officer for the Missouri Department of Mental Health. She says that, while it may seem like an 18, 20, or 22-year-old is able to make adult decisions, they are not developmentally ready just yet. This is because the brain’s frontal lobe, especially the prefrontal cortex, isn’t fully mature until around age 25.

The development of the pre-frontal cortex of the frontal lobe allows us to process the pros and cons of a decision before it is made. “It lets us to do things most animals cannot,” explains Dr. Stanislaus. “Decision making, logical thinking, reasoning — all of those things happen because of the frontal lobe.”

a young student smiling and holding a model of the human brain.

The prefrontal cortex is associated with planning and problem-solving. MIT’s Young Adult Development Project explains that it connects all parts of the brain. “The prefrontal cortex communicates more fully and effectively with other parts of the brain, including those that are particularly associated with emotion and impulses, so that all areas of the brain can be better involved in planning and problem-solving.”

So, what does this mean for young adults? And why is it important for students, parents, and teachers to understand brain growth and development?

Think about the brain’s development under the umbrella of what kinds of decisions typically face teens and young adults. For example, with an under-developed brain, they may be more inclined to speed without thinking of the consequences, such as getting a ticket or causing an accident when they are driving in a hurry. If they are out with friends and presented with alcohol or drugs, they may not think about the short-term and long-term consequences of this behavior – what it means to fail a drug test at work, develop an addiction, or the legal consequences of substance use.     

The Role of Parents

While time is necessary for optimal brain development, there are things parents can do to help their child until their brain reaches full maturity. A story about young adult brain development by Today.com encourages parents to help their child maintain independence by taking responsibility for themselves in school and at work. If they ask for your advice in solving a problem, don’t solve it for them; instead, get them to build their own problem-solving skills by asking what they think they should do or if there is another way to handle the issue. Encourage them to reach out to an advisor on campus if they need additional help.

There are ways parents can help train the brain much earlier. Encourage your child to find a job, which can build decision-making skills and allow young adults to thrive in different situations. Your child can become better at money management and understand the consequences of their actions.

Staying Involved and Engaged

smiling father hugging happy teen son while he doing homeworkIt is important to create a level of excitement for kids at a young age, whether it’s through a job, hobby, sports or another healthy activity. Otherwise, the young mind tends to gravitate towards unhealthy ways of achieving enjoyment, such as risk-taking behaviors. 

“Because the prefrontal cortex is not developed, kids are not thinking about the consequences of their actions because they are just enjoying the experience,” explains Dr. Stanislaus. She says that for 14 and 15-year-olds, it is critical for parents and schools to foster productive, positive experiences for them, such as sports or other healthy communal activities. Kids who are more involved in such activities and have more structure to their day are less likely to do drugs and engage in risky behaviors, compared to kids who do not have structure to their day.

With the development of the prefrontal cortex happening through the mid-twenties, it’s not difficult to see that, as college students grow older, their behaviors change. “With freshmen and sophomores, they are more focused on having a good time and don’t think much about the consequences. Getting to all their classes and keeping good grades are not often a priority for them,” says Dr. Stanislaus. But by the time they are seniors, they have different behaviors, and are more focused on their careers. That behavior continues through their twenties as they plan for their future. They are much more responsible, looking more closely at their career paths, and determining life goals.

Tech and Young Minds

Girl gamer sits in profile with her phone in her hands.Today.com reinforces that while young adults are capable of making decisions, “They must work harder than mature adults to stay focused, make responsible choices and avoid risky behaviors. 24/7 access to technology via smart phones and the Internet can impact developing minds. “The developing brain is often overwhelmed by information overload. And while the brain is still developing, this can lead teens and young adults to appear unfocused, not goal-oriented, and to engage in risky behaviors.”

Dr. Stanislaus points out that social media consumption can have a negative effect on kids. Those who spend more time on social media have a higher risk of anxiety and depression. This is because they are always seeking likes and comments for social approval and validation, and the fear of missing out makes them feel insecure.

Social media also lessens face-to-face interaction and the good feelings that comes with it. Dr. Stanislaus stresses how vital it is for teens and young adults to socialize in person. “Human beings need engagement and interaction,” she says. “With social interaction from working in school or on projects with partners, there is a joy that is created, and they need that joy. Social media cuts away time in engaging in social activities that can bring happiness.”

The Takeaways

The most important thing parents should do, says Dr. Stanislaus, is to support their young adult as their brain develops. Kids are going to make mistakes — even when they are well into their twenties. Give them freedom, but help them understand the consequences of that freedom, while reinforcing positive behaviors. Show them ways to work through problems. If they do cross the line, talk through what happened and allow them to face the consequences within a safe structure. Allow mistakes to be made, but help your child learn from them.