Tom McCall, left, and Stefan Adegbola in Royal Shakespeare Company’s “Titus Andronicus.” “Pretty much every night there’s somebody who faints or is sick,” said Becky Loftus, the R.S.C.’s head of audience insight. “We want to see how the audience reacts physically to the production.” Credit Helen Maybanks/RSC

Does watching a production live, versus on a movie screen, engender a different physiological reaction? The RSC intends to find out. More.