PD Dr. Leo Hermle was Chief Physician in the Christophsbad Hospital, Göppingen for 25 years. Beyond psychiatric basic work he has a history in entactogen and psychedelic research. For the „Handbook Psychoactive Substances“ ((von Heyden, Jungaberle, Majic 2018 in Springer Publishers) he contributed two papers. In this video in German language Leo Hermle talks about:
The paper Flashbacks und anhaltende Wahrnehmungsstörungen nach Einnahme von serotonergen Halluzinogenen (authored by Tomislav Majic, Timo T. Schmidt, Leo Hermle) is about a rather rare, but serious pathology when it comes to recreational uses of psychedelics. In his short video, he explains HPPD and what the paper is about.