Carl August Wickland (1861–1945) was a 20th-century Swedish-American psychiatrist and psychical researcher. Wickland turned away from conventional medical psychology and toward the belief that psychiatric illnesses were the result of influence by spirits of the dead. Wickland came to believe that a large number of his patients had become possessed by what he called "obsessing spirits", and that low-voltage electric shocks could dislodge them, while his wife Anna acted as a medium to guide them to "progress in the spirit world".