Summary: He took larvae (caterpillars), split them into two groups, and offered them sugar water and sugar water with lavender scent in it. The ones feeding on the lavender scent were then given a mild electric shock that make them vomit so they associated it with something bad. Then in their adult phase he offered the same two choices and the plain sugar water group went 50-50 to the choices whereas the shocked/lavender group went to the plain sugar water 80% of the time.

While looking into it I found references to studies on this dating back to at least 2008, studies on larval neural changes and fruit fly studies. They studied memory retention in moths also.