Nature, trying to catch up with Science’s synaesthetic, describes Musical imagery: Sound of silence activates auditory cortex:
Auditory imagery occurs when one mentally rehearses telephone numbers or has a song ‘on the brain’ — it is the subjective experience of hearing in the absence of auditory stimulation, and is useful for investigating aspects of human cognition1. Here we use functional magnetic resonance imaging to identify and characterize the neural substrates that support unprompted auditory imagery and find that auditory and visual imagery seem to obey similar basic neural principles.
The same part of the brain is at work when you fill in a short gap in a song (“Satisfaction” or the Pink Panther theme) as when you are hearing it. That’s wild, though not surprising. When you remember an image, your brain does what it would do if you were looking at the image.
Science is so neat.