This Is a slight off shoot from the project but very helpful to understand on how to act out and present your character, as I said in an earlier blog, the actor would have masks to hide their main facial expression, while the mask its self has the expression on, the actor had to use his body language to express the feeling of the mask.
When I came to do this in drama my self, we used masks with NO expression, I remember the teacher saying that the idea was to catch the eye of the audience. The experience was hard as you had to use your hole body, but fun.
(the masks and is quotes from http://www.theatrehistory.com/italian/commedia_dell_arte_001.html)
"In the course of the development of the Commedia dell'arte, there grew up certain traditions which held fast for many years. The rascally servant, the old man, the lady's maid, and the like--stock characters which appeared in every play--always wore a conventional dress, with masks. In general these masks may be classed under four or five groups: Pantalone and the Doctor, both old men; the Captain, a young man of adventure; the valet or jester, usually called Zanni; the hunchback Punchinello; and another old man, somewhat different from the first two."
Matt this research is not off topic it is in fact an excellent example of telling a story through posturing rather than verbal and facial expressions. It's a great link that you have made through differing areas of the arts; and as you are working with a mushroom it is very relevant in understanding how your story can be told.