A Child’s Brain on Puberty: Brain Development During Adolescence
It isn’t just children’s bodies that are changing during puberty. Their brain goes through a reorganization process as well, pruning away connections and reorganizing itself to boost efficiency. This brain development has been likened to a second birth, or something akin to the terrible twos, and can leave adolescents a bit discombobulated.
Brain changes that occur during puberty
Adolescent brain development
Puberty ushers in a reorganization of the brain. Old neurons are killed off, new ones are born, and neural connections become more placid, paving the way for new connections. “What we’re increasingly learning is that there’s another node of new plasticity around the time puberty starts,” says pediatrician Ronald Dahl. (Denworth, 2021) The brain also begins adding more myelin (white matter) to existing connections, boosting the speed with which signals travel.
This reorganization helps increase the brain’s efficiency and boosts their cognitive functioning, but in the interim, things can get a bit messy. It’s almost like your child’s brain were a construction zone. It can leave them feeling a bit out of sorts or even lead to regressions in maturity. (Jensen, 2006)
Part of the problem is that this growth isn’t linear: “The limbic system, a collection of brain areas that are sensitive to emotion, reward, novelty, threat, and peer expectations, undergoes a growth spurt,” writes Lydia Denworth, “while the brain areas responsible for reasoning, judgment, and executive function continue their slow, steady march toward adulthood. The resulting imbalance in the developmental forces helps to explain adolescent impulsivity, risk taking, and sensitivity to social reward … ” (ibid)
Risk taking & rewards
The adolescent brain becomes more sensitive to rewards and gratification, prompting youth to seek higher levels of novelty and stimulation. As Eric Jensen states, “Risks, rewards and fun are driving their brain.” After puberty youth are more likely to become thrill seekers and risk takers, which once again is part of nature’s design, intended to push children out into the world. We see this same shift in all species, not just humans. (Natterson-Horowitz & Bowers, 2019)
Family connections weaken while peer connections become more important
Studies find that in kids ages 7 to 12, brain regions involved in detecting rewards and paying attention activate more profoundly to mom’s voice than an unknown woman. But as kids go through puberty and enter adolescence, the situation is reversed: Their brains show greater activation in response to a stranger’s voice than moms. This shift tends to occur between the ages of 13 and 14. In other words, teens tune you out, and connections with peers and others become prioritized over family connections.
“Just as an infant is tuned into a mom, adolescents have this whole other class of sounds and voices that they need to tune into,” says neuroscientist Daniel Abrams. (Sanders, 2022) This doesn’t mean parents are no longer relevant, far from it. It’s just evidence of this shift in a youngster’s brain from seeking parental approval to craving peer approval. Unfortunately, antisocial behavior also increases as a result of peer influence. (Bixenstine, DeCorte & Bixenstine, 1976)
How hormonal changes during puberty affect the brain
Levels of sex-related hormones surge during puberty. A boy’s testosterone can spike to levels 18-times higher or more than what they were before puberty. Girls also experience significant spikes in both testosterone and estrogen, though their hormones are a bit more stable.
This doesn’t just make adolescents horny, it can alter their brain and change the expression of their emotions and experiences. They pick up things they didn’t notice before. “There’s information flowing by us all the time,” says neuroscientist Linda Wilbrecht. “Once puberty and hormones pass through the circuit, suddenly these cues have meaning. They don’t have salience until you shift into the adolescent phase.” (Denworth, 2021) One of the best descriptions I heard of this development is that it’s like seeing an all new spectrum of colors they couldn’t see before. Emotions feel deeper and the world becomes more vivid.
Awareness increases
Puberty ushers in a profound increase in children’s awareness, both of themselves and the larger world around them. They start thinking more independently, questioning what they’ve been told and forming their own unique perspectives. In fact, since the perspectives of younger children are formed almost exclusively on the basis of what their parents tell them, you could argue puberty brings about the first truly independent thinking in children.
Their brain becomes more unique
In line with the previous principle, the neural wiring of children’s brains become more differentiated from one another during adolescence. In other words, youth become a more unique person.
Children’s sleep cycles shift during puberty
During puberty, a child’s circadian clock will shift by a couple of hours, meaning they get tired later at night than before and will want to sleep in later into the morning than they used to. (Scientific American, 2023) Unfortunately, public school schedules trend in the opposite direction, and so youth become more sleep deprived.
See also: