• Resting Potential - an unstimulated nerve ("polarized")
• Graded Potential - a charge too weak to fully stimulate the nerve
• Action Potential - a fully stimulated nerve ("depolarized")

Acetylcholine - involved with voluntary movement

Monoamines:

• Dopamine - inhibits behavior; associated with pleasure, psychosis and drug addiction
• Serotonin - controls sleep, appetite; associated with emotions
• Norepinephrine - excitatory; affects arousal, alertness and learning

Endorphins - opiate-like substance that plays a role in pain relief

GABA (gamma-aminobutyric acid)- A very abundant neurotransmitter which causes a neuron not to fire, causing an inhibitory response. This system is affected by drugs such as barbiturates, alcohol and benzodiazapines.