The internet and social media have recently gained interest in frontal lobe development. TikTok users have claimed they knew when their frontal lobe had developed, with many claiming frontal lobe development gave them a whole new perception of their lives. It came with a novel life view, clarity, and maturity. It is seemingly unanimous that the age of 25 is cited as this revolutionary turning point. Social media users reflected on a newfound judgment of past risky behavior and the behavior of younger acquaintances. Others compared the feeling to the dust of youth finally settling and an overwhelming wave of calm, as they are mentally detached from unnecessary stressors and witness a shift in their perception of their future. Some under the age of twenty-five have clung to their not fully developed frontal lobe as an excuse for certain actions. Some people above the age of 25 simply put it as terrifying.
It's an easy rabbit hole to fall down. More and more videos are telling you that upon your 25th birthday, you will wake up, and the world will make sense. Instilling a sense of hope and maybe impatience in people nearing the age. But what exactly is your frontal lobe? When does it develop? And what happens during its development? Does everything you’ve ever been confused or upset about suddenly float away like a released balloon? Do song lyrics become significantly less relatable as you no longer ponder past relationships or anxieties? And does the future become all that much clearer? These are the questions this blog aims to answer and debunk, as I share what research has established is actually happening in your brain during frontal lobe development and navigate how this may connect to and disprove social media’s claims on the subject.
Who you are: The Frontal Lobe
If you were to take your index finger and place it in the center of your forehead, that’s where your frontal lobe is. Nestled behind layers of skin and skull, located at the front of the brain is the portion of your brain responsible for high-cognitive function. The right hemisphere of the front lobe is responsible for control of the left part of your body, and vice versa. In total, the frontal lobe takes up one third of your cerebral hemisphere. So what exactly does this big chunk of brain do? A lot! Its responsibilities cover self-control, memory, emotional expression, problem solving, language, judgment, sexual behaviors, and communication. It is essentially the “control panel of your personality” (Healthine, 2023a).
Your frontal lobe is the center for the emotions and thought processes that ultimately translate into who you are. It is the piece of your brain where the neurons firing and synaptic connections being made are the defining pieces of what makes you, you (Healthline, 2023a). But you aren’t simply born with these connections pre-established. The frontal lobe does not fully mature until roughly around the age of 25, social media got that bit correct (Healthline, 2023b). But you don't just become a new version of yourself on your 25th birthday in the same way who you are wasn’t determined the minute you were born. Our brain learns who we are, and there’s a lot of things that happen both inside and outside your brain that lead up to that 25th birthday, and the supposed prophesized enlightenment that may come with it.
What Fires Together, Wires Together: Your Remodeling Era
During development in the womb, as many as 250,000 new neurons are created each day. By the time we are born, our brain contains billions of neurons and trillions of premade connections. So much so, that an infant brain actually contains far more neurons than the adult brain (Duke, 2014). By the mere age of six, your brain has reached 90 to 95% of its adult size. From that point onward, peaking between the ages of 13 to 15, the developments and changes made are simply a “remodeling” of your brain (Healthline, 2023b).
The fundamental underline of brain growth and development is the construction and strengthening of regional neurocircuitry and pathways (Arain et al, 2013). The limbic system hits the finish line first. By the ages of 10 to 13 your limbic system which is responsible for memory storage/retrieval, regulation of autonomic processing, and expression of emotions has finished developing (Healthline, 2023b).
The mesolimbic system, the reward center of the brain, additionally undergoes significant changes. This is the region of the brain where there is an abundance of dopamine releasing neurons, which fire upon anticipating a reward. As it develops, primarily in teenage years, the mesolimbic system has higher dopamine levels. This can result in thrill seeking behavior in adolescence.
Finally, the prefrontal cortex, the largest portion of the frontal lobe, and the reasoning center of the brain, is the last area of the brain to remodel and fully mature. Once it has matured, you are henceforth considered capable of discerning the relationship between your actions and their consequences, whether they be short term or long term.
This is the significant difference between an adolescent and mature adult brain. Beyond physical remodeling and connections, there is a consequential shift in risk assessment. In our adolescence and as teenagers, we have heavily relied upon the amygdala, our center of emotions, to guide and make decisions. The amygdala is the home to primitive urges, impulses, fears, aggression, and emotions. Simply put, in the same situations where an adult responds rationally and with anticipation of future consequences, the adolescent brain, fuelled by emotional gusto, seems to run toward “acting before thinking things through”. Our brains are inherently emotionally impulsive. That is, until we train them not to be. (Healthline, 2023b).
While these major pieces of the brain’s development, especially the frontal lobe, have fallen into the focus of social media and popular discussion, another important process is responsible for defining and developing our brain. This process, although tiny in perspective, makes a hugely defining difference in what makes who you are (Healthline, 2023b). It has everything to do with the increasing connectivity and unconscious edits being made across your brain. What you see as your day to day life, your developing brain sees as a day at the gym. Your morning routine, picking up that pencil, or smiling at a stranger on the street, is single handedly affecting all the small stuff in your brain, in a big way (Johnson, Blum, & Giedd, 2009)
Growing Up Is A Million Tiny Goodbyes: Pruning, Myelination, and Grey Matter Reduction
Your brain can and is constantly changing. At any age, you can learn, grow, adapt, and change. Human beings are capable of continuing to develop across their entire lifespan, given the right circumstances and environment. This is thanks to neuroplasticity (Netzley, 2022).
Everytime you experience something, an electrical impulse triggers either the formation of a brand new synaptic connection or the strengthening of an existing one. Whether that’s going for a run on your favourite route, or trying a new food. Our brains are consistently being changed by the strangers we brush against and the way we live our lives.
Your brain enjoys what it knows. Activities that require less energy to perform, are enabled by a strong synaptic connection, thus, the task comes easier to you. The neural connections we do not strengthen through use, weaken and atrophy as our brain prunes away what it determines we simply don’t need (Netzley, 2022).
Pruning is when the brain gets rid of neurons and synapses. Synapses are structures that build pathways connecting neurons allowing them to communicate (Healthline, 2023b). Simply put, “cells that fire together, wire together”. Neuronal connections that are strengthened through repeated experience, are preserved while less useful connections are pruned away. This process sculpts the neuronal network based on a person’s unique experiences (Duke, 2014). What you do over and over again becomes ingrained in the structure of your brain, and you maintain it physically, as a part of who you are (Netzley, 2022).
This process occurs twice during development. First in early childhood between the ages of 2 to 10 and again during late adolescence from your teens to late 20s (Healthline, 2023b). This pruning causes the brain to lose significant amounts of grey matter (Wnuk, 2024). But for everything you lose, a step in development is taken.
While the brain undergoes pruning it is additionally strengthening connections through myelination. Myelination is when neurons are wrapped in an insulating layer of protein called myelin. This sheath enables neurons to make effective and speedy communication across the brain. The production of myelin increases in adolescence, speeding up the flow of information throughout your brain, and making everything you perceive and experience feel really big in perspective (Healthline, 2023b). Myelination increases the brain’s white matter. White matter volume continues to increase until around the age of 40 when it peaks. In adolescence, most connectivity is localized, areas of the brain that neighbor each other, work together to complete cognitive tasks. But as your brain develops, as a consequence of the surge in white matter volume and novel connections, there is an extraordinary bloom in connections between initially widely separate functions across brain areas, building a more widely distributed network of neural connections (Wnuk, 2024).
For the frontal lobe, increased white matter and connectivity is responsible for higher-level cognitive abilities and control. Making the adult brain better equipped to suppress impulses and more maturely plan, problem solve, and come to informed decisions. (Wnuk, 2024). These connections are defining emotional and cognitive processes, our ability to regulate and interpret emotions, and what is colloquially termed as emotional maturity (Johnson, Blum, & Giedd, 2009).
Differences in Development Rate Between Males and Females
Another fixation by social media is that frontal lobe development differs between girls and boys. It has long been stated that girls mature faster than boys (Laureys, 2021). Females enter the adolescent period around 10-11 years, while male enter at around 11.5 years. This difference in maturation, follows suit in brain maturation with frontal lobe grey matter peaking at 11 in females, and 12.1 in males (Laureys, 2021).
In a study on brain development during childhood and adolescence, volumes of white and cortical gray matter were quantitatively analyzed, across boys and girls aged 4.2 to 21.6 years. It was found that frontal gray matter peaks approximately one year earlier in females, corresponding with female’s earlier age of onset of puberty (Giedd et al., 1999).
25. The End?
In adulthood, it is felt that the more developed frontal lobe guides more rational decisions. Situations are afforded better judgment and responded to with accounting for long-term consequences and an understanding of how decisions being made now could affect a multiverse of potential futures (University of Rochester Medical Center, 2024). So. Is the age of twenty-five such a miraculous transformation point? This age is roughly when the frontal lobe finishes developing, shifting from impulsive, emotion-based decision-making to more thought-out and reasoned reactions and conclusions. But in our adolescence, can we use our undeveloped frontal lobe with certainty as an excuse for present actions as we wait for that promised shift in which the world seems to click into place? And should we be scared of that seeming sudden loss of adolescence? Simply put? No.
If you wake up in the morning and feel like you can’t be bothered to do that thing that you know is good for you and will benefit you in the long term, if you let negative patterns that cause you harm into your life repeatedly or if you hear those words leave your mouth and it's stupid, but you sum it all up to being young and naive, you’re giving your developing brain a kick in the shin.
As we’ve established. Your brain learns you. It knows your day-to-day habits and routine and builds stronger neuronal connections based on those repeated, consistent actions. If you choose continually, the easy, emotionally guided decisions, that you know aren't great but give you that dopamine-adrenaline rush in the short term, you single handedly strengthen a tiny synaptic connection in your brain. You’re making it easier for you to give in to that habit in the future, making it a more challenging trend to break, and probably most overlooked of all, that other connection, that connection where you made a different choice, is growing weaker. Every day, you feed your brain information about who you are. Those steps lead up to the full development of your frontal lobe. It’s your late teens and early 20s that I would argue are potentially more meaningful and impactful to your frontal lobe’s development and which are going to make you see a significant shift in your perception of your life, love, clarity, maturity, and sense of calm than when you finally do turn 25.
Social media, as we all have come to know, is a double-edged sword. Although your frontal lobe’s development may be trending on TikTok, be cautious and aware that because information becomes widespread, it is not always being passed along for validity. I hope this blog brought more information to those dwelling on frontal lobe development and placed some facts beside the growing fascination.
And who knows, maybe you will wake up on your 25th birthday, and the world will genuinely make infinitely more sense as your anxiety floats away, and the future seems as plausible and potential as ever. But until then, I encourage you to train your brain to go about life with a sense of “maybe.” Maybe instead of doing that thing, I do every day that I’m not so sure is beneficial to me in the long run, maybe I’ll try something new. Maybe we make the most of our adolescent emotional brain and savour the time spent listening to Gracie Abrams and crying over sappy rom-coms. Maybe we make a little whisper in our brain every time we lean on a habit, and instead of saying, well, that's just my undeveloped frontal lobe, say, maybe I'm going to change that. See how your brain does with maybes in the meantime, appreciate the process of growing and becoming, because the brain you're waiting so patiently on to develop is taking its most meaningful steps this very second.
References
Arain et al. (2013). Maturation of the adolescent brain. Neuropsychiatric Disease and Treatment, 9, 449-461. doi: 10.2147/NDT.S39776
Duke (2014). Module 3: Alcohol, Cell Suicide, and the Adolescent Brain. Retrieved from: https://sites.duke.edu/apep/module-3-alcohol-cell-suicide-and-the-adolescent-brain/
Giedd et al. (1999). Brain development during childhood and adolescence: a longitudinal MRI study. Nat Neurosci 2, 861–863. doi: 10.1038/13158
Healthline. (2023a). Frontal Lobe: What to Know. Retrieved from https://www.healthline.com/human-body-maps/frontal-lobe
Healthline. (2023b). This Is How Your Brain Develops in Your Teenage Years. Retrieved from https://www.healthline.com/health/teen-brain-development
Johnson, Blum, & Giedd. (2009). Adolescent Maturity and the Brain: The Promise and Pitfalls of Neuroscience Research in Adolescent Health Policy. Journal of Adolescent Health, 45(3), 216-221. Doi: 10.1016/j.jadohealth.2009.05.016
Laureys et al. (2021). The Effects of Age, Biological Maturation and Sex Development of Executive Functions in Adolescents. Front Physiol, 12, 703312. doi: 10.3389/fphys.2021.703312.
Netzley, M. (2022). What Fires Together, Wires Together. Medium. Retrieved from https://michaelnetzley.medium.com/what-fires-together-wires-together-163fa2e62d8d
University of Rochester Medical Center. (2024). Understanding the Teen Brain. Retrieved from https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=1&ContentID=3051
Wnuk, A. (2024). When the Brain Starts Adulting. Brainfacts.org. Retrieved from https://www.brainfacts.org/thinking-sensing-and-behaving/aging/2018/when-the-brain-starts-adul ting-112018
留言