Retrieval failure (due to absence of cues) encoding specificity principle (Tulving and Thomson)context-dependent forgetting; context at encoding and retrieval do not matchAbernethy - student study; familiarity increased attainmentstate-dependent forgetting; state at encoding and retrieval do not matchOverton - drunk v. sober study; same state = better scoreInterference theorysimilar memories interfereproactive interference; old learning disrupts recall of new; Underwood word lists - earlier words learnt better retroactive interference; new learning disrupts old; e.g. new phone number but not old one