The Adolescent Brain

Frontline: Inside the Teenage Brain•http://www.pbs.org/wgbh/pages/frontline/

shows/teenbrain/

The Brain• Weighs about 3 pounds

• “The most complicated mass of matter in the known universe.”

• Contains over 10 billion neurons and another 100 billion support cells.▫ Eventually forms over

100 trillion connections.

• Brain controls ALL activity

• Constantly changing and adapting

• Neurons are capable of re-routing circuits

Terminology• Neurons:

▫ Specialized cells that transmit information to other nerve cells or muscles.

• Axon:▫ An electricity conducting

fiber that carries information away from the cell body.

• Dendrite:▫ Receives messages from

other neurons

• Synapse:▫ Contact point where one

neuron “communicates” with another neuron.

Source: Sullivan, 2006

Source: University of Utah, 2006

Brain Development

•2 stages:▫Growth spurts or overproduction of

neurons▫Pruning

•Growth spurts are seen at younger ages•Pruning happens during adolescence

▫“Use it or lose it”

BRAIN STRUCTURES

• Frontal Lobe• Parietal Lobe• Temporal Lobe• Occipital Lobe

• Cerebellum• Corpus Callosum• Brain Stem

Source: University of Utah, 2006

Source: University of Utah, 2006

Frontal Lobe

•Responsible for:▫Personality, judgment, reasoning, problem

solving, rational decision making,▫Logic and understanding of consequences▫Governs impulsivity, aggression,▫Organizing thoughts, planning for the future

▫Undergoes significant changes during adolescence Not fully developed until mid-20’s.

Prefrontal Cortex•Part of the frontal lobe:

▫Helps with impulse control, judgments, reasoning

▫One of the last areas of the brain to develop fully.

▫During this time, there is an increased need for: Structure, mentoring, and guidance from adults

Temporal Lobes

•Control hearing, understanding speech, sorting new information and short-term memory

•Contains:▫Amygdala and hippocampus

•Matures around 18-19 years of age.

The Teenage Brain

•Underdevelopment of frontal cortex leads to:▫More “gut” reactions than reasoning

More likely to use amygadala (emotions) than prefrontal cortex (reasoning) for information processing.

▫It takes experience to train the brain.