Endellving, mashhur psychologist va neuropsyologist, inson hotirasi tū katta xavf ega tadqiqotlar o'tkazgan. U explicit va implicit hotira tushunchalarini kiritgan. Tulving semantics va episodic hotiralar farkini tushuntirib, epizodik xotirani shakhsning shakhsiy tajribalari bilan boglangan deb tariflagan.