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 collaborated with psychologist Pierre Janet (1859–1947) to study neurosis and psychosomatic issues. Together, they wrote "Neuroses and Fixed Ideas" and "Obsessions and Psychasthenia".