1. THE BRAIN AND THE EFFECTS OF ALCOHOL AND OTHER DRUGS

2. THE BRAIN  Command center of your body  Weighs about 3 pounds  Different centers which control different things  Despite being 90-95 percent of its adult size by age six, the brain is still “under construction” until age 18.

3. BRAIN STEM  Vital life center  Breathing, swallowing, heart beat, sleeping  Things you never think about  Gulping large amounts of alcohol in a short time can stop the breathing reflex and cause death

4. CEREBELLUM  Responsible for things you learn once and never have to think about again  Walking, riding a bike, throwing a ball  Higher thought processes like music and complex math problems  Changes drastically during teen years, increasing its number of nerve cells and connections to the rest of the brain

5. CEREBRAL CORTEX  Also known as CEREBRUM  Divided into right and left hemispheres  Thinking part of the brain- most highly developed  Store and process language, math and strategies  Also contains the LIMBIC SYSTEM  Responsible for survival  Causes you to be hungry for good food and to enjoy the company of others;  Emotions related to fear, anger and love

6. LIMBIC SYSTEM  Hippocampus and Amygdala  Memory vDrugs can have powerful control of the brain stem and limbic system. These systems can override our cortex in controlling our behavior.So, we do things without thinking!

7. NERVE CELLS AND NEUROTRANSMISSIONS  NEURON- three parts  Cell body that directs all activities of the neuron  Dendrites that receive messages-many fibers  Axons that send messages-long single fiber

8. NEUROTRANSMISSION The transfer of a message (electrical impulse) from the axon of one nerve cell to the dendrites of another No direct contact. There is a chemical release (neurotransmitters) into the space between the axon and dendrites. This space is called a synapse. The neurotransmitters bind to receptors in the dendrites.

9. NEUROTRANSMITTERS Chemical messengers, carrying information from one neuron to another.

10. MYELIN  A fatty substance that covers axons.  The more myelin an axon has, the faster nerve impulses can travel. –After puberty, the amount of myelin in the brain increases dramatically, making the brain much more efficient.

11. ADDICTION AND THE BRAIN The brain is wired so if something is pleasurable, you will tend to do it again. Life sustaining activities, such as eating, activate nerve cells devoted to producing and regulating pleasure.The neurotransmitter involved is called DOPAMINE. The pleasure circuit (dopamine system) spans the brainstem, emotional limbic system and the frontal cerebral cortex

12. ADDICTION Drug addiction alters the way the pleasure center, as well as other parts of the brain, functions. Almost all drugs affect chemical neurotransmission –Heroin and LSD mimic natural neurotransmitters –PCP blocks receptors

13. –Cocaine interferes with getting neurotransmitters back where they belong –Methamphetamines cause too many neurotransmitters to be released Prolonged drug use causes addiction.