4.3.1. Predisposing factors for developing MH
MH is a rare phenomenon: although estimates vary across studies, less than one percent of population who have acquired hearing loss develop MH (Cope & Baguley, 2009). We first consider why some people but not others with acquired hearing loss develop complex hallucinations of music and why complex auditory hallucinations in acquired hearing loss preferentially take the form of music rather than other percepts such as speech or environmental sounds.