Occasional Collaborators of Kronfeld
Heinrich Köbcke, M.D.
In 1919, he worked as an assistant physician in Kronfeld's department and later on became a neurologist in Berlin. In his practice, Max Hodann, a co-worker at the Institute, ran a medical health centre.

Gerhard Scherk, M.D.
He did research on the "Psychology of Eunuchoids". In 1925, he was officially registered as a doctor and worked as an internist and an assistant physician at the Rudolf-Virchow-Hospital, Berlin, in 1928.

Kurt Messing, M.D.
He did research for his doctoral thesis on "Dependence and Jealousy among Homosexuals". Later on, he went into private practice as a psychologist and homoeopath in Berlin.

Lida Wolkowa, M.D.
The Bulgarian doctor consulted the Institute for her doctoral thesis on "Spiritism and Schizophrenia".

Theodor Friedrichs
He researched in Kronfeld's department on the "Psychology of Hypnosis and Suggestion".

Walter Lurje
His research was directed at the supposed connections between "Mystical Thinking, Mental Illness and Modern Art" as well as between "Autism and Buddhism".