Alvin Lucier is still making music four years after his death – thanks to an artificial brain

In a darkened room, a fractured symphony of rattles, hums and warbles bounces off the walls – like an orchestra tuning up in some parallel universe. If you look closely there is a small fragment of a performer. In the centre of the room, visitors hover around a raised plinth, craning to glimpse the brains behind the operation. Under a magnifying lens sit two white blobs, like a tiny pair of jellyfish. Together, they form the lab-grown "mini-brain" of the late US musician Alvin Lucier – composing a posthumous score in real time.