Post-mortem brain specimens from documented heroin, cocaine, and heroin-cocaine polysubstance users as well as normal control subjects were collected within approximately 24h after death as part of the routine autopsy process under a protocol approved by Wayne State University's Human Investigation Committee. Cause and manner of death were determined after medicolegal examination by the Medical Examiner. The general characteristics for the Study I subjects (N=29; n = 7–8/group) are described in Table 1 and Supplement 1.
