There is supporting evidence for proactive and retroactive interference; a typical study of this is called the paired-associate technique which is where two word lists are given and learning one list interferes with learning the other, such as that done by Underwood.
In a study into memory done by Tulving and Pstoka to support the theory of interference they found that the participants given one or two lists remembered a higher percentage of words than those who were given more lists in terms of free recall. This is evidence of retroactive interference.
But when the participants were then given a cue to which list to recall the participants remember about 70% of the words regardless of how many lists they were given. So it may be that the interference effect may not show what is really in the memory, it was shown by the results that the participants remembered more words with a cue, this is known as cue-dependant forgetting. This therefore suggests that it is possible to recover from interference.
The retrieval failure and cue-dependant forgetting explanation to forgetting in the long-term memory suggests that the reason why people forget is because they cannot access the memories that are stored. And that people can remember these things when they are given a cue, there are either external or internal cues.
Abernethy did some research to support external cues or context dependant learning/forgetting. A group of students were tested before they began a course and then every week from that point. Two groups of the students were tested in the room they learnt in either with their usual teacher or with a different teacher. The other two groups of students were in a different room with either their usual teacher or a different teacher. It was thought that the familiar things like the teacher or room would act as a cue to the student remembering. And the results of these tests showed that the students tested in the same room with the same teacher performed best.
Goodwin et al. did a study to support internal cues or state-dependent learning/forgetting. Goodwin found that people who drank a lot forgot things when they were sober but once they returned to the state of being drunk they remembered what they had forgot, this is an internal cue. Other research on this is by Miles and Hardman who found that when people learned a list of words while on an exercise bike they remembered them better when they exercised again then when they was at rest.
But does this explanation relate to everyday memory, everyday memory is more procedural. Many of the studies into cue-dependent forgetting are laboratory-based so this may affect the results and draw them further away from real life.
Such as after a while remembering how to play a game like ping pong you may not remember all the rules and such but you remember most and re-learn the rest, although there is the re-learning to do cues don’t explain it.