ACh

muscle and memory

TOO LITTLE Alzheimers

TOO MUCH

Dopamine

pleasure

TOO MUCH schizophrenia

TOO LITTLE parkinsons

Serotonin

mood and arousal

TOO LOW Depression

Norepinephrine

control alertness and arousal

GABA

Major inhibitory

TOO LOW seizures

Glutamate

major excitatory

TOO HIGH may be related to anxiety

Endorphins

perception of pain and pleasure

Substance P

Pain perception.

TOO HIGH chronic pain