TED Talk - Mysterious Workings of the Adolescent Brain

Sarah Jayne Blakemore
15 years ago, we considered mental development to happen in the first few years of life. Thanks to MRI, we can take a "snapshot" of the brain at different ages. We can use functional MRI to take a video. This has radically changed how we see brain development. Adolescence is actually the age where major brain development happens. The pre-frontal cortex is much bigger in humans, and does cognitive functions, inhibiting inappropriate behavior, social interaction, self awareness. This goes through a dramatic change in adolescence. Grey matter peaks at the age of puberty. Then it goes down, which means that synapses (connections in the human brain) strengthen and others are thrown out. It fine tunes ideas.
Humans are great at reading body language and translate it into human emotions. The Medial Pre-frontal Cortex, is more active in adolescents than in adults when they make social decisions.
Adolescents have been stereotyped, and there are reasons why:
Risk-taking: Especially in groups, adolescents are more likely to take risks. The Pre-frontal Cortex is still in development, and it stops risks. Another part of the brain is still large, and it rewards risk.
Poor impulse control
Self-consciousness