While researching beliefs about sorcery in mesoamerica, I've come to
notice an association between the liver and anger that is surprisingly
pervasive. The link is easily found in the beliefs of several cultures
with minimal or no cross contact: Nahuatl speaking peoples,
traditional Chinese medicine, medieval, Greek, Arabic, and Indian
medical lore, Pacific island cultures, etc. It would be natural to
assume that there is some reason for this remarkably common
association. My first thought was a common liver illnesses might
result in physical symptoms similar to extreme anger such as bulging
eyes, etc. Or perhaps rages and fits are common to people suffering
from liver illnesses that have been diagnosed and studied by Western
medicine. Can someone find a definitive anthropological or medical
article that studies this common association and which has been
published in a reasonably well respected professional journal or other
publication ? The article in question must study this cross cultural
phenomenom OR / AND give me a precise situation that may lead to this
common observation.

I'll just note that the word bilious reflects the connection
you've observed. The connection isn't difficult to make for
anyone into natural and alternative therapies.

A person who is physically toxic is much more likely to be
irritable and irate, and the liver is what cleans the toxins
from the blood (which, by the way, symbolizes the consciousness).
If the liver is overloaded due to unmanageable toxicity, it is
likely to become diseased, and that level of toxicity is more
likely to be seen to affect the person's temperament negatively.

The word 'melancholy' also refers to the liver. Melancholy means black
bile, ostensibly coming from the liver when one is angry!

Yes, indeed, although in classical Greek medicine, a choleric
temperament was related to the yellow bile:
http://en.wikipedia.org/wiki/Choleric

"Can someone find a definitive anthropological or medical
article that studies this common association and which has been
published in a reasonably well respected professional journal ..."