Sleep Medicine Expert Dr. Murray Experimented on MJ

10/13/2011 1:47 PM PDT BY TMZ STAFF

Sleep expert Dr. Nadar Kamangar -- who called Dr. Conrad Murray's treatment of Michael Jackson "inconceivable" -- told prosecutors today ... Murray used MJ as his own personal guinea pig for dangerous medical experiments.

Kamangar -- an adviser for the CA Medical Board -- testified that Propofol was never approved for use as a sleep aid when Murray used it to treat MJ's insomnia ... claiming Murray's treatment amounted to "an experiment."

Murray's attorney J. Michael Flanagan cited a Taiwan research study today from 2010, in which 64 patients with insomnia were successfully treated with Propofol -- but Kamangar pointed out ... the study took place after MJ's death ... in a safe hospital setting.