Composer Sergei Rachmaninoff (1873-1943) wrote his Piano Concerto No. 2 after professional hypnotic treatment.
Following the disastrous premiere of his First Symphony in 1897, Rachmaninoff suffered severe depression and creative torpor.To treat this condition, he was persuaded in 1900 to visit Dr. Nicolai Dahl, who used hypnosis to help him start composing again.
The treatment worked, and Rachmaninoff's Second Piano Concerto, which premiered to great acclaim in Moscow in 1901, is dedicated "to Dr. Dahl."