The foremost writer and thinker at the crossroads of psychoanalysis and the occult is and probably always will be Carl Jung. Which brings up the question of what is the “occult.” I would say that much of what goes under the name of the occult today is related more to “psychoanalysis and horror.” To the degree that this work touches on the occult it is in the area of the “oc-cultural": that which is covered by artists like Mike Kelley, Tony Oursler, Jim Shaw, David Lynch - surrealism and weird America. Although I love these artists and have been influenced by them in my own work, this idea of the occult is a recent - and perhaps third - version of the occult.
We had this discussion about the concept and term “occult” at our recent conference on “Psychoanalysis and the Occult” - which one can access here: analytica.org/events/psychoanalysisandtheoccult. The first main aspect of the occult explored by the early psychoanalysts in their practice - including Freud - was part of the burgeoning research on the paranormal and parapsychology - including telepathy, seances, hypnosis, etc - performed in a seriously scientific way. Eisenbud, Fodor, and Stevenson continued this work in psychoanalysis. It was “occult” because it was considered taboo, fringe and unacceptable in professional circles.
The second main dimension of the occult concerns the work on magick and mysticism being done by the theosophists, freemasons, Crowley, Steiner, and others in an equally scientific but still occult - in the sense of hidden - way. Both traditions drew from historical cultural forms of Eastern and Western psychic practice - such as buddhism, taoism, yoga, qabalah, gnosticism, alchemy, and anthropological research. Devereux and Roheim focused on this aspect of psychoanalysis and the occult. It was occult because it was other - non-Western, non-civilized.
Since there is a lot of confusion regarding what the “occult” is, and even negative connotations to the signifier, I wanted to provide some clarification. There are innumerable further references for those interested.