Psychedelics in Psychiatry

Hello to all. Was it interesting to do research on real psychopaths (serial killers) using psychedelics or cannabis?
did their thinking and vision of the world change under or after not taking one-time active substances?

Such studies could open up a new side (psychedelics and marijuana) of these substances. And mozhet to give us to understand and understand the behavior of all these people (psychopaths).

just an interesting thought