How clear is your inner voice? Do you internally narrate your life? And do you get songs stuck in your head?

Almost all of us can imagine sounds in our minds. But a small part of the population don't have internal auditory imagery — a phenomenon called anauralia.

Today, we explore the experience of anauralia, in an episode from Radio New Zealand's Our Changing World.

Our Changing World is produced and presented by Claire Concannon and Ellen Rykers for RNZ.

The original version of this episode was first broadcast on RNZ as The puzzle of the silent mind.

Special thanks to Auckland University Student Chamber Orchestra, for allowing use of their recording of Beethoven's 5th symphony.