In the early 1920s, Thompson became interested in Freudian psychoanalysis and he underwent analysis with Dr. Philip S. Graven in 1923. In 1924, Thompson became vice-president of the Washington Psychoanalytic Association, but by 1936, after criticizing the American psychoanalytic establishment for straying too far from Freud, he was no longer listed as a member of the association. It was Thompson's contention that lay analysts should be given as much importance in the psychoanalytic field as physicians. Sigmund Freud's collected correspondence in the US Library of Congress does contain a 1923 postcard to Joe Tom Sun, listed in the collection as an alias for Dr. Thompson of Baltimore, M.D.
