Smells Like Teen Synapses: A Look Inside Adolescent Brains and Behaviors

“I would there were no age between sixteen and three-and-twenty, or that youth would sleep out the rest; for there is nothing in the between but getting wenches with child, wronging the ancientry, stealing, fighting…”

The old shepherd’s thoughts from Shakespeare’s A Winter’s Tale resonate centuries later when we consider examples of stereotypical teenage behavior – emotional outbursts, angst, and recklessness just to name a few.  But if we dismiss teenagers as lacking emotional discipline, we fail to understand the complex neural underpinnings that drive much of this behavior and allow a concerned adult to guide teens through this critical stage of brain development.

Smells Like Teen Synapses: A Look Inside Adolescent Brains and Behaviors

In a keynote address to the New York Academy of Sciences, psychiatrist Ronald Dahl, presented adolescence as a dualistic period of vulnerability and opportunity.  The vulnerability can be described through the 200 percent mortality rate increase from childhood, with homicides, suicides, and accidents accounting for the vast majority (85 percent) of these deaths.  The opportunities within this same period emerge from a theoretical interaction between environmental influences and adolescent neural plasticity.  As the brain develops, training in cognitive skills such as long term planning can reinforce neural pathways that support those skills.  An experience like working to save up money for a first car or attending regular soccer practice, may improve a teenager’s ability to set goals and work towards them, thus making him or her more likely to repeat this behavior in the future.

Plasticity is the ability of the brain’s neurons to alter their reciprocal connections – e.g., forming new or more efficient connections in response to new stimuli or learning.  Just before puberty, children undergo a wave of synaptogenesis, a rapid formation of new synapses, or neural connections, in the brain.  By puberty, the density of dendritic spines (small knobs which receive signals from axons) in the prefrontal cortex is two to three times greater compared to that of adults.  While many of these synapses are gradually pruned across adolescence, neuroscientists theorize that the sheer volume of connections increases the brain’s adaptability to make experience-based changes during childhood and adolescence.


New synapses are either strengthened or eliminated based on an individual’s experiences.  Connections and pathways that are activated more frequently get reinforced and are more likely to remain through adulthood, while those accessed less frequently are lost across the teenage years.  When thinking about the role of the prefrontal cortex (where much of this synaptic reorganization occurs) in supporting functions like problem solving, self-regulation, decision making, and long term planning, one can begin to see the implications for teenage behavior.  Realizing such implications may help parents and teachers ease the transition from adolescence to adulthood.

As Shakespeare duly noted, adolescents are popularly known for their emotionality.  Research indicates that while the repertoire of emotions experienced is comparable to adults, it is the increased intensity of these experiences that sets teens apart from their elders.  Adolescents are thus keenly sensitive to emotional stimuli. One study found that teens (compared to children and adults) demonstrated a weaker ability to resist emotional face stimuli in a go/no-go task.  This task requires pressing a button for emotionally neutral faces while deliberately not pressing the same button when an emotional face was present.  Teens were more likely to make a mistake by pressing the button upon seeing an emotional face.  Additionally, there was a marked increase in metabolic activity in the ventral striatum, a brain region also associated with the reward system, whenever teens saw an emotional face.  Not only were the emotional stimuli difficult for the teenagers’ button-pushing fingers to ignore, but it was also pleasing to see the emotions.

The good news for parents, teachers, and Shakespearean shepherds is that emotional regulation does seem to increase with age, and it is a teachable skill.  The more teens are guided through the process of monitoring and tempering their emotions, the more they improve, as the neural connections that support emotional regulation are strengthened and maintained.

Mindfulness training techniques such as focused breathing and meditation have shown promising results, both reducing teen stress and lowering the amount of interpersonal conflicts.  Clinical protocols like practicing emotional control while role playing aggravating situations – pretending someone is making fun of you, for example – have also been effective in reducing behavior problems in schools and reducing the frequency and intensity of angry outbursts.

As an educator who works in many middle and high schools, I can attest to the sheer volume of patience it takes sometimes to calmly manage adolescents at their most… adolescent. I am also comforted in the thought that, via such methods, we can guide teens through potentially tumultuous times, while also influencing the very shape of their synaptic-selves.


Escrito por Colin O’Neal

Images made by Jooyeun Lee



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