As Koko experiments with her new electronic muscial keyboard, Dr. Penny Patterson helps with the controls, which can change the sound to play a number of different instruments.
Besides sign language and art, music offers another potential form of interspecies communication – though it is probably more effective at conveying emotions than thoughts. Also, the most resonant communication media seems to be an individual thing. For example, Koko seems to prefer sign language to art, while her late silverback companion, Michael, preferred art and music to words.