Adolescent Brain Development And What It Means

Content Warning: Please be advised that the following article mentions trauma, substance use, and other potentially triggering subjects. Read with discretion. 

Trying to understand your teen can feel frustrating and confusing. You may not comprehend the reasons behind your child's behavioral and mood changes. 

Some unpredictable behavior can be explained by looking at adolescent brain development. When you consider how quickly an adolescent's brain is changing, it may give insight into why their behavior may seem so out of the ordinary. The adolescent brain is still growing and does not stop until 25, and many teens and young adults experience heightened information-processing abilities along with social sensitivity. 

If you are struggling with understanding your teen's mood, behavior, or personality changes, researching adolescent brain development may help you learn more and support your child through development. 

How Brain Development Works

From birth, our brains constantly evolve as neural pathways become more robust and communication becomes more efficient. As babies, our brains overproduce neurons (the cells responsible for communicating messages in the nervous system) and build extensive neural pathway connections. Then, throughout early childhood, some connections are strengthened while others are lost. 

You might think of this process as pruning a tree: it grows stronger and produces more as certain parts are trimmed back. In neuroscience, this pruning is called brain remodeling, where unused connections are removed. By the time a child is six years old, their brain is already 90-95% the size it will be as an adult. 

The same process happens again just before puberty and extends until early adulthood. The brain undergoes significant growth and development in adolescence with intensive brain remodeling. During this time, the brain rapidly develops, strengthening those valuable connections and ridding itself of others.

Brain development happens through a "use it or lose it" principle. For example, if you use a particular piece of knowledge or skill, the neural pathways associated with it may become stronger. However, if you do not, these pathways might not be formed. This process could partially explain why teenage students have difficulty learning a second language in the classroom after age 17. Without the opportunity to practice, the brain might not have the chance to create pathways for this knowledge.

Teen Brain Development

The emergence of MRI (magnetic resonance imaging) in the 1970s made it possible to visualize the brain in real time and observe how specific parts of the brain "light up" when engaged in particular types of tasks. This discovery also allowed neuroscientists to observe and compare images of the brain at different ages. Scientists found that the prefrontal cortex area of the brain undergoes considerable development during adolescence.

The developing brain forms from the back and works its way to the front. The prefrontal cortex is located at the front of the brain, just behind your forehead. It is the last part of the brain to develop. Accordingly, the development of the prefrontal cortex is not finished until we are in our mid-twenties. The prefrontal cortex is responsible for reasoning, impulse control, working memory, and rational decision-making. This part of the brain can significantly impact adolescent brain development and decision-making.

This part of the brain is part of the limbic system and is associated with emotion, impulse, instinct, and aggression. The limbic system helps to direct behavioral and emotional responses, especially those related to survival (i.e., fight or flight, feeding, reproduction, etc.). 

This system is fully developed in adolescence and plays a crucial role in decision-making. The amygdala and the limbic system are responsible for reward-seeking behavior, motivating teens to seek their peers' social approval and other emotional rewards. The discrepancy in the development of these different parts of the brain can mean that adolescents face challenges when making decisions.

As close as they are to a fully developed adult brain, your teen might have rational discussions with you on complex topics. They may understand the nuances of various controversial issues and grasp complex concepts. However, without a fully developed prefrontal cortex, teens may be susceptible to impulse, often led by their emotions and the desire for social approval. This impact can make level-headed people still prone to risk-taking when emotionally charged. 

The consumption of substances can also impact the developing brain. Studies show teens are more prone to binge drinking than adults and may experience substance dependency. If you or your child is struggling with substance use, contact the SAMHSA National Helpline at (800) 662-4357 to receive support and resources.

The Impact Of Stress And Trauma

Because the teen brain is developing rapidly, it can be vulnerable to the effects of trauma and stress. Teenagers are at risk of encountering trauma. Their risky behaviors as they seek to define themselves and achieve independence might put them in conflict with parental or other authority figures. Family trauma, such as divorce or the passing of a loved one, can leave them vulnerable or uncertain.

Studies show that trauma has a negative impact on childhood brain development. It can slow the development of the prefrontal cortex, pushing adolescents to rely even more on their amygdala and limbic system. This process can make it difficult for them to articulate their emotions or explain their reasons for behaving in a certain way.

If you're a teen or child experiencing or witnessing abuse of any kind from a families or caregiver, reach out to the Child Help Hotline at 1-800-422-4453 or use the online chat feature.

Words Of Caution

While these facts about brain development can explain some of a teen's behavior, try to guard against generalization. The maturation of the adolescent brain is also influenced by their environment, heredity, hormones, and the uniqueness of their genetics. Even adults may engage in impulsive or risky behaviors. You might find a wide range of personalities and behaviors within any age group. Try not to make predictions about behavior based on defining features like age. Many teens may be responsible, mentally healthy, and goal oriented. 

Advice For Parenting Your Developing Teen

Considering this knowledge about your adolescent's brain development, you may wonder about the best parenting methods. Below are a few guidelines to keep in mind. 

Maintain Firm Boundaries, Limits, And Consequences

Your teen may appear mature and sophisticated, and there may be moments when you think they can handle adult freedom. However, try to remain cautious. Without a fully developed prefrontal cortex, your teen's brain could be vulnerable to instant gratification and the need for approval. Maintain boundaries and rules and help your teen make safe choices. 

Expose Your Child To Positive Activities And Influences

With a brain still under construction, teens' activities may profoundly shape their development. Pay attention to what they do with their time. If they spend most of their time scrolling social media or playing video games, consider helping them develop other hobbies. Challenging but enjoyable activities like music, sports, or theater might positively affect the way an adolescent's brain develops as they enter adulthood.

Provide Opportunities For Healthy Risk Taking

Teens sometimes seek an outlet for impulsive and risk-taking behaviors. By allowing them to try out new experiences and activities, you may give them the opportunity to embrace risk in a way that is safe and healthy.

Get To Know Your Child's Peer Group

When you are not with them, the behavior of your teen's peer group might impact their decisions and behaviors. Be aware of who they are hanging out with and educate them on healthy relationships. 

Assist Your Child In Finding Ways To Express Feelings Creatively

Your teen may struggle to articulate their emotions without a fully functioning prefrontal cortex. Encourage them to find an outlet for their emotions through dance, music, writing, or other hobbies they enjoy.

Teach Your Teen Real-Life Skills

Their brain may not be fully developed yet, but your teen may want to know that you support their transition into adulthood. Teach them practical skills like changing a tire, cooking a meal, and creating a budget. These skills could increase their confidence in future success.

Seek Professional Help

Understanding that your teen's behavior and emotional reactions may be rooted in their developing brain can be a first step in forming a solid relationship with open communication between you.  However, if you feel unable to manage your teen's behavior or struggle with communication, reach out for help from a licensed professional therapist. 

Life can get busy, especially during the teenage years, and you or your child may feel more comfortable talking to a provider from home. In these cases, online treatment could be beneficial. Research supports online therapy for teens with anxiety, depression, and behavioral issues. Interventions can help teens learn healthy communication and improve their overall mental health. Additionally, online therapy can allow you or your teen to choose between phone, video, or live chat sessions with your licensed therapist. 

As a parent, if you hope to reach out for mental health support, consider a platform like BetterHelp. If you have a teen aged 12-19, they may benefit from a platform like TeenCounseling that serves their age group. No matter your choice, reaching out for support can be a brave first step for anyone of any age.