As most jazz lovers know, the high point of a concert is when the musicians let loose and improvise, “talking” to each other with their instruments. Indeed, modern jazz owes a lot of its appeal to pioneers like pianist Art Tatum (photo above) who introduced improvisation into the art form. Scientists have long suspected links in the brain between music and language, although just what they are isn’t clear. In a new study, researchers recruited 11 professional jazz pianists to engage in sessions of what musicians call “trading fours”—a form of improvisation in which two soloists alternate playing four bars of music each, riffing off of each other’s spontaneous creations. The musicians took turns having their brains scanned with a functional magnetic resonance imaging machine while playing on an all-plastic keyboard (metal parts would be attracted to the fMRI’s powerful magnet), while their partners played within earshot. The scans showed that during the sessions, parts of the brain linked to language syntax—the structural way that words are put together to make sentences—were activated; but brain areas linked to language semantics—the actual meaning of words and sentences—were suppressed. The team concludes today in PLOS ONE that language and music partly overlap in the brain because they both employ the same syntactical neural circuits, but communicate meaning in very different ways: language verbally, and music nonverbally. This may be why music lovers often feel keenly that they know what the musician is saying, but can’t put it into words.