Musical ear syndrome (MES) refers to auditory hallucinations subsequent to hearing loss. It is comparable to Charles Bonnet syndrome (visual hallucinations by visually impaired people) and some have suggested this phenomenon could be included under that diagnosis. The occurrence of MES has been suggested to be very high among the hearing impaired. Sufferers typically hear music or singing and the condition is more common in women. The hallucinatory experiences differ from psychotic disorders although there may be some overlap.
The likely cause is a small cerebrovascular event affecting the auditory cortex. The ‘hole’ in the hearing range is ‘plugged’ by the brain confabulating a piece of information – in this case a remembered melody. A similar occurrence is seen with strokes of the visual cortex where a visual field defect occurs and the brain confabulates a piece of visual data to fill the spot. Towards the end of his life, Robert Schumann said he heard angelic music and music from other composers, which formed the basis for his violin concerto (however, his symptoms may also have been caused by syphilis or mercury poisoning).