Addiction and the Teenage BrainLearning Target: I can explain how addictive substances work in the brain, creating tolerance, dependency and addiction.Do Now: Write one question about addictive substances (tobacco, alcohol, illegal drugs and prescription drug abuse) and/or addiction on the board. We’ll come back to it in the Pair/Share. Lecture: Write at least 2 questions, answers or comments.HW: See last slide.

How do addictive substances interact with your brain?

• They connect with the pleasure centers of our brains.

• Many addictive substances raise the levels of dopamine and serotonin, which regulate our feeling of pleasure and well-being.

These Addictive Substances Increase Dopamine and/or Serotonin Levels

Dopamine • Heroin, Oxycontin,

Vicodin, mimic dopamine• Alcohol causes excessive

dopamine release

• Nicotine prevents dopamine breakdown so it sticks around longer

Serotonin• Amphetamines and

Ecstasy cause excessive serotonin release

• Cocaine prevents Serotonin Re-uptake so it sticks around longer (incidentally so do anti-depressants such as Zoloft, Paxol, etc.)

Addictive Substances and the Rewards Pathway• The rewards pathway is activated by pleasurable stimuli.

Examples—Sex, love, success, your favorite meal, etc. Addictive substances mimic those experiences.

Stage 1: Tolerance• The brain defends itself against the artificially higher levels

of dopamine and serotonin by blocking some neuro-receptors, thus lowering the intake of dopamine and/or serotonin.

• The next time the addictive substance is taken, a higher dose is required to achieve the same effect.

Stage 2: Dependence • Neurons adapt to repeated exposure to an addictive substance and start to only

function normally in its presence. Dopamine levels fall below normal, leaving a feeling of reduced pleasure from ordinary life. This fuels a psychological need to get high again, just to feel something.

• When the substance is withdrawn, the body reacts negatively. Withdrawal symptoms can be mild (caffeine), unpleasant (heroin) or even life threatening (severe alcoholism— “The DTs”).

• The substance becomes necessary to feel normal. Not “high” just “normal.”

Stage 3: Addiction• Addiction: Continually engaging in a compulsive behavior,

even when faced with negative consequences (loss of family, job, etc.).

• Loss of control over intake of the addictive substance. Can lead to overdoses.

• Has both physical and psychological components.

PAIR/SHARE: Analysis

Did your question from the start of class get answered? Do you have any other questions that have come up since then? Share one question with your partner and then speculate together about possible answers.

A Recovering Addict Thinks About Cocaine

Nature Video Cocaine Video

Front of Brain

Back of Brain

Amygdalanot lit up

Amygdalaactivated

Even years into a recovery, the mere mention of cocaine or an image of cocaine use can trigger intense cravings on the part of an addict.

In a globalized, highly competitive economy, every neuron counts!

• Your brain contains over 100,000,000, 000 neurons, which relay chemical and electric signals to other parts of your brain.

• Unlike other cells of the body, neurons do not reproduce after birth.

• We are born with all the neurons we will ever have. On a purely biological level, they are, essentially, who we are. Damaging them or altering how they work lowers our potential and changes who we are, usually not for the better.

Addiction is a significant contributor to crime and damages families and individuals

• 18% of current inmates committed a crime in order to acquire drugs.

• 68% of local jail inmates were found to be dependent on drugs or alcohol or abusing them.

• 19% of probationers said they had arguments with their family, friends, spouse, or boyfriend/girlfriend while under the influence of drugs.

• 25% of jail inmates said they had been in a physical fight while under the influence of drugs.

Assignment

• Write 1 page or draw a cartoon (see illustration rubric) summarizing how addiction works in the brain.

• You can complete this for HW, but you must begin in class.