1. Acetylcholine Muscle action Learning/Memory Decreased levels associated with Alzheimer disease

2. Dopamine Movement Learning, attention Emotion Excess associated with schizophrenia Decreased levels associated with Parkinson Disease

3. Serotonin Mood, hunger, sleep, arousal Decreased levels associated with depression

5. Norepinephrine Helps control alertness/arousal Decreased levels associated with depression

6. GABA “gamma-aminobutyric acid” Major inhibitory neurotransmitter Decreased levels associated with seizures, tremors, and insomnia

7. Glutamate Major excitatory neurotransmitter Involved in memory Excess associated with overstimulation, seizures, and migraine headaches

8. Endorphins Released in response to pain and exercise Basis for ‘runner’s high’ Prescription narcotics are potent agonists

9. Divisions of the Human Nervous System