With psychologist Pierre Janet (1859–1947) he performed studies on neurosis and psychosomatic disorders. With Janet, he co-wrote "Névroses et idées fixes" and "Les obsessions et la psychasthénie".
He worked alongside psychologist Pierre Janet (1859–1947) on research into neurosis and psychosomatic conditions. They co-published "Neuroses and Fixated Ideas" and "Obsessions and Psychasthenia".