Kenneth Sperry on Instagram: "Grover Cleveland “Cleve” Backster Jr. was an interrogation specialist for the Central Intelligence Agency, best known for his experiments with plants using a polygraph instrument in the 1960s which led to his theory of primary perception where he claimed that plants feel pain and have extrasensory perception, which was widely reported in the media. 🌱The Experiment: Backster connected a Dracaena plant to a galvanic skin response (GSR) meter — the same device used in