Somnambulism in Verdi's Macbeth and Bellini's La Sonnambula: opera, sleepwalking, and medicine.

The arts can provide unique ways for determining how people not directly involved in medicine were viewing and informing others about physical and mental disorders. With operas, one need only think about how various perturbations of madness have been portrayed. Somnambulism has long been a particularly perplexing disorder, both to physicians and the laity, and it features in a number of operas. Two mid-nineteenth-century masterpieces are examined in detail in this contribution: Verdi's Macbeth and Bellini's La Sonnambula. In the former, the sleepwalking scene is faithful to what Shakespeare's had written early in the seventeenth century, a time of witchcraft, superstition, and the belief that nocturnal wanderings might be caused by guilt. In Bellini's opera, in contrast, the victim is an innocent girl who suffers from a quirk of nature, hence eliciting sympathy and compassion. By examining the early literature on somnambulism and comparing this disorder in these operas, we can see how thinking about this condition has changed and, more generally, how music was helping to generate new ways of thinking about specific diseases and medicine.