It is established that we learn more than we typically recall. Failure of retrieval of memory is an interpretation of forgetting. There are several variables that affect retrieval. Three of these variables are distinctiveness of the memory, practice of retrieving the memory and the presence of effective retrieval cues.

Distinctiveness is when we remember well events that distinctively stand out from the background of the rest. Memories with flashbulbs are well recalled although not accurately. This is because they represent events that are distinctive from others in our lives. When we recall better an item that differs from the remaining items in a list, we call this Isolation effect or Von Restorff effect. Distinctive events are retrieved better because we uniquely target a single memory when prompted to recall. For example when we are prompted to recall the world Trade bombing, this prompt cues a very particular memory.

Testing effect is experienced when retrieval is facilitated by previous retrieval. When students take a test shortly after learning, the recall is greatly enhanced on a later retest. In studying Testing Effect, the general idea is to test shortly after learning and then retest sometime later. The recall on the later test shows interesting results because they are better than the results of the of the test done shortly after learning. The effects of prior testing are greater if the same test is given both times and more difficult prior testing is more effective. When initial free recall test is given, it produces better retrieval later than an initial cued recall test.

Hypermnesia is a good demonstration of testing effects because it is remembering that improves over successive attempts at reproduction of the studied material. Hypermnesia is the opposite of forgetting (amnesia). The reason for remembering more and not less across successive tests is because additional tests give more time to retrieve. Also people prompt their memories with self generated cues that help them remember different things at different times. The self prompting cues vary across successive tests because different things come to mind at different times and so these cues help tap items that could have not been adequately cued on the earlier tests.