Hyperacusis is a rare hearing condition in which a person perceives everyday sounds to be abnormally or uncomfortably loud. The condition can affect one or both ears. In some cases, it occurs suddenly ...

For most of us, the hum of a refrigerator, the clatter of plates or a nearby conversation are just background noise. But for some, these sounds are uncomfortable, distressing or even painful.

As the father of two deaf sons and the author of a book on the history of cochlear implants, I thought I knew a bit about hearing problems. I was still shocked by an e-mail I received some months ago.