Question

What evidence shows that the amygdala is involved in the emotion of fear?

Answer 1

Most evidence of physical brain functions are now verified by various observations of brain activity during stimulus with devices such as a CAT/PET scans and EEG.

Explanation:

Most evidence of physical brain functions are now verified by various observations of brain activity during stimulus with devices such as a CAT/PET scans and EEG.

http://www.ninds.nih.gov/disorders/misc/diagnostic_tests.htm

http://neuroscience.uth.tmc.edu/s4/chapter06.html

See also the following link for mapped brain areas.
http://www.mybraintest.org/brain-function-areas-structure-map/