Amygdala

Location

The Amygdala are almond shaped groups of nuclei located in the medial temporal lobes of the brain.

Function

Fear Conditioning

The amygdala mediates fear conditioning; an arbitrary CS is associated with a fearful US - initially the US will produce a fear reaction and the CS will not, however after pairing the CS will produce a fear reaction too.
Conditioned fear is abolished by amygdala lesions, or by glutamate antagonist injections into the amygdala.

Appetitive Conditioning

Similarly to fear conditioning, the amygdala controls dietary conditioning (random CS with food US); the theory is it associates sensory information with appetitive approach reactions.