Dr. Helen Morrison displays sections of John Wayne Gacy’s brain April 29, 2004. | AP https://chicago.suntimes.com/2018/12/14/18416340/where-john-wayne-gacy-buried-the-bodies-more-key-sites-tied-to-serial-killer https://www.alamy.com/slices-of-john-wayne-gacys-brain-displayed-by-serial-killer-expert-dr-helen-morrison-dr-helen-louise-morrison-1942-an-american-forensic-psychiatrist-and-writer-john-wayne-gacy-jr-1942-1994-an-american-serial-killer-and-rapist-during-the-1970s-image328357534.html Note the top brain slice, specifically the butterfly shaped hole and the brain structure dividing the two halves, the pellucidum septum.  The septum is divided in the middle by an opening, the cavum. From my https://pathwhisperer.info/2014/12/09/psychopathy-marker-neurodevelopmental-marker-for-limbic-maldevelopment-in-antisocial-personality-disorder-and-psychopathy/: Psychopathy marker … Continue reading John Wayne Gacy’s brain