Company founder Trisha Brown has been a choreographer since the 1960s, yet — like many gifted people toiling in her art form — she’s a force in New York and other dance-centric metropolises, while remaining lesser-known to the hoi polloi. Aside from her contributions to postmodern dance, Brown has more recently made an interesting leap into directing opera. She’s a visual artist to boot, and that’s always an interesting dimension to bring to the challenge of conceiving and mounting expressive stage pieces of any kind. Here, Brown’s ensemble performs a mixed repertory, including Pygmalion, based on French composer Jean-Philippe Rameau’s 1748 operatic adaptation — itself based upon Ovid’s interpretation of a Greek myth. This is another Great Performances at Vanderbilt program that delivers to Nashville what it can’t have too much of: exposure to art that strives to move well beyond the status quo.