that through genetic manipulation. when the neurons are being externally activated because they've been exposed to an odor the flies associate that odor with an imaginary electric shock so the yoda serves as a warning signal the odor creates an artificial and traumatic memory despite the fact that nothing happened to cause it the manipulation of a few neurons creates the illusion of an electric shock and the unpleasant memory associated with it. indeed the next time that the fly is exposed to this node tries to get away from a. professor turn him otoh believes that these artificial memories are not merely an end in themselves