New York Times has an article about musical hallucinations. It's a problem that mainly afflicts older people, and particularly those who are partly deaf. I hadn't thought of it as a problem myself -- I hallucinate music sometimes, and I never thought of it as a problem, just slightly weird. It's always music that I've been hearing a lot of recently (not usually my own, oddly enough -- it usually seems to be music my son or partner have been playing a lot). In any case, I always assumed it was simply my brain hearing something it couldn't interpret (a not infrequent occurrence; I suspect I'm a touch deaf), and "filling in" with the closest familiar thing. This latest research seems to bear out my assumption. Full-blown auditory hallucinations are apparently more annoying than my own experience, however, and the rise in cases may reflect the much more constant musical background in our lives.