How the Brain Works The Facts Visually Explained by DK (z-lib.org)

THE PHYSICAL BRAIN

Older Children and Teenagers

Older Children

and Teenagers

Teenage brains undergo dramatic restructuring.

Unused connections are pruned, and insulating

myelin coats the most important connections,

making them more efficient.

Teenage behavior

Teenagers have a reputation for being

impulsive, rebellious, self-centered, and

emotional. A lot of this is due to the changes

happening in adolescent brains. Human brains

change and develop in set patterns, leaving

teenagers with a mix of mature and immature

brain regions as they grow. The last area

to fully develop is the frontal cortex, which

regulates the brain and controls impulses.

This area allows adults to exert self-control

over their emotions and desires, which is

something adolescents can struggle with.

Synaptic pruning, which is when

unused neural connections die off,

starts during childhood and

continues through our teen years.

Cortical areas are pruned from the

back to the front. Pruning makes

each area more efficient, so until it

is finished, that region cannot be

considered fully mature.

SYNAPTIC PRUNING

IMMATURE MATURE

Sleep cycles

During our teenage years, we need plenty of sleep as our brain

continues to develop. But at this time, our circadian rhythms shift

as melatonin, the hormone that is released in the evening and

makes us feel sleepy, begins to be released later than usual. This

is why teenagers often want to go to bed later than children and

adults and may struggle to get up for school in the morning.

Risk-taking

Pleasure-seeking parts of

teenagers’ brains are well

connected, but impulse-control

mechanisms are underdeveloped,

which can lead to risk-taking.

Frontal

cortex

KEY

Out of sync

Waking teenagers early for

school is like giving them

constant jet lag. Studies

have shown that starting

school an hour later

improved attendance and

grades. Fights and even car

accidents also decreased.

Adult sleep time

Adolescent

sleep time

Noon Midnight Noon

Onset of

sleep occurs

later in

teenagers

than in adults

Onset of

sleep in

adults

Teenagers

wake later

in morning

than adults

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