Have you ever heard your recorded voice played back and thought, “Surely that’s not what I sound like”? I know I have. Claire O’Connell writing in today’s Irish Times attempts to answer the riddle of why when we hear our own voices when we speak, it is different to how others hear it.
One plausible explanation is that we have additional “internal hearing” when we speak. In his book, The Odd Body , Dr Stephen Juan explains the concept, citing speech therapist and diction coach Dr Nelson Vaughan.
When you speak, the pharynx in your neck sends out sound vibrations. Some of these travel through the air, and both you and other people hear those sounds when they enter the ear from the outside. That’s also what microphones pick up. But some of the vibrations you make when you speak spread instead through the inside of your head. This sound also reaches your inner ears, but it is conducted by bone rather than air.
As otolaryngologist Prof Timothy E Hullar points out in Scientific American, the mechanical properties of your head enhance the deeper vibrations of those “internal” sounds as they travel. So in essence, when you speak, you hear your own voice through two pathways: one external, one internal. You hear both, but others only hear the part conducted through air.
Similarly in recordings, the air-conducted sounds are picked up, but not the internal vibrations. So when it’s played back you hear yourself as others hear you.
So now you know!