In the wild world of social media, memes about the frontal lobe “developing at 25” have taken over Instagram and TikTok feeds.
You must have seen them: a chaotic Gen-Z making impulsive decisions, captioned “Me at 24: YOLO (You Only Live Once) vs. Me at 25: Frontal lobe unlocked and suddenly making practical decisions.” Or the smug one-liner: “He’s over 25 and still acts like this? Guess that frontal lobe’s on vacation.”
These viral jokes tap into a myth about brain maturation. But as cognitive scientist Dr. Jazlyn Nketia, who holds a PhD from Brown University, explained in her recent Instagram reel that this idea is misleading. As she put it:
“Please, please, please stop saying that your prefrontal cortex forms or comes online when you turn 25.”
The frontal lobes are the largest cortical regions of the brain, making up about 40% of the cerebral cortex. They include key areas such as:
The medial frontal region
The dorsolateral region
The frontopolar region¹
Each area handles specific roles including motor control, speech, executive functions (planning, decision-making, impulse control), and behavior regulation.¹
The prefrontal cortex (PFC): a crucial part of the frontal lobe and the brain’s command center for higher-order functions. It manages incoming information, selects appropriate actions based on goals and context, and integrates feedback from rewards or punishments through fronto-subcortical neural circuitry.²
This circuitry shapes everything from basic motor responses to complex decision-making and motivated behavior (approach vs. avoidance). Disruptions here are linked to disorders like ADHD and broader psychopathology.²
In short: The frontal lobe isn’t a dormant section that “activates” at 25, it has been working since birth and constantly refining its connections.
Development of the frontal lobe is critical for:
Cognitive Processes: executive function, attention, memory, and language 4
Emotional and behavioral regulation: managing approach/avoidance behaviors that guide motivation
Contextual decision-making: weighing risks, rewards, and long-term consequences
Social and moral behavior: self-awareness, as well as social and moral reasoning 4
The prefrontal cortex is one of the last regions to reach full maturation, which explains some behavioral immaturity in adolescents and young adults. Its extensive connections with subcortical structures make its functions complex and vulnerable to disruptions.²
This is the core of the viral myth.
The prefrontal cortex undergoes prolonged maturation, with major processes such as synaptic pruning, myelination, and circuit refinement continuing through adolescence and into the mid-20s. Many studies3 note that executive functions tend to stabilize “near the age of 25,” referring specifically to the prefrontal cortex.
However:
There is no magic switch at age 25 where the brain suddenly “comes online.”
The PFC is always present and active; it’s not “offline” before 25.
Brain development is gradual, variable, and lifelong.
The meme version implies that people under 25 are neurologically incapable of rationality which is misinformation. Adolescents and young adults can and do make mature decisions.
As Dr. Nketia emphasized:
“What’s actually happening is that your prefrontal cortex, like any other part of your brain, is always present, always active, and always changing over the course of your life.” And she adds ,“As a cognitive scientist, I implore you, please stop spreading this misinformation.”
The frontal lobe and prefrontal cortex handle some of the most human aspects of cognition: decision-making, self-control, and goal-directed behavior. They mature gradually into the mid-20s on average, but they’re active and changing throughout your entire life.
1. Wildstein, Sara, and Silvana Riggio. “Seizures of the Frontal Lobes: Clinical Presentations and Diagnostic Considerations.” In Executive Functions in Health and Disease, edited by Elkhonon Goldberg, 405–19. Academic Press, 2017. https://doi.org/10.1016/B978-0-12-803676-1.00017-9.
2. Rosch, Keri Shiels, and Stewart Mostofsky. “Development of the Frontal Lobe.” In Handbook of Clinical Neurology, edited by Mark D'Esposito and Jordan H. Grafman, vol. 163, 351–67. Elsevier, 2019. https://doi.org/10.1016/B978-0-12-804281-6.00019-7.
3. Arain M, Haque M, Johal L, et al. Maturation of the adolescent brain. Neuropsychiatr Dis Treat. 2013;9:449-461. doi:10.2147/NDT.S39776
4. Chayer C, Freedman M. Frontal lobe functions. Curr Neurol Neurosci Rep. 2001 Nov;1(6):547-52. doi: 10.1007/s11910-001-0060-4. PMID: 11898568.