Forgetting

Interference is when two pieces of information are in conflict. Forgetting occurs in the long term memory because memories cannot be accessed even though they are available. There are two types of interference: proactive interference and retroactive interference.

Proactive interference is when old information interferes with new information.

Retroactive interference is when new information interferes with old information.

Interference is worse when memories are similar. This could be because the previously stored information makes new information more difficult to store or because new information 'overwrites' previous memories that are similar.

AIM                          To invesitigate the effects of similarity on interference

PROCEDURE                 Participants were asked to learn a list of words and recall them to 100% accuracy. They were then given a new list to learn. The new list varied in the degree to which it was similar to the old list in each group. Group 1 were given synonyms (words had the same meanings as the original list); group 2 were given antonyms (words had the opposie meanings to the original list). Group 3 were given a list of unrelated words; group 4 were given a list of nonsende syllables. Group 5 were given three-digit numbers and group 6 acted as a control group and were not given a new list.

FINDINGS              It was found that performance depended on the nature of the second list. The synonyms had the worst recall. When participants were given very different material the average number of items recalled increased.

CONCLUSION            Interference is strongest when memories are similar.

Evidence from lab studies demonstrates inference in memory - Most of the studies carried out into interference show that both types of interference are very likely causes of forgetting from the long term memory. Lab experiments control the effects of extraneous variables - High validity

Real-life studies have supported the explanation - Baddeley and Hitch (1977) asked rugby players to recall the names of teams they had played so far in that season. Accurate recall depended on how many games had been played since rather than how long the match took place. This shows that interference can be applied to some real life situations - High external validity

Research uses artificial materials - The stimulus material used is usually word lists. This is different from things people remember in everyday life, although it is more realistic than consonant syllables. In everyday life people remember things such as peoples faces and birthdays. The use of artificial materials makes interference more likely in a lab. It may not be the cause of everyday forgetting - Lacks ecological validity

Time periods in research - The time allowed in studies between learning lists of words and recalling them are quite short. Research reduces the experience of learning into a short time which does not reflect how people learn and remember information in real life situations. This means that the conclusions from the research cannot be generalised to outside the lab - Lacks ecological validity

Interfernece effects may be overcome by cues - Tulving and Psotka (1971) gave participants five lists of 24 words each organised into six categories. Categories were not explicit but it was assumed they would be obvious when presented. Recall was 70% for the first list; this dropped for each additional list. When a cue was introduced recall of the additional lists rose back up to around 70%. The conclusions made from this is that interference prevented access to the memories of the words. When given a cue it was easier to access the forgotten words

ABSENCE OF CUES

Lack of cues can lead to retrieval failure. When information is initially placed in the memory associated cues are stored at the same time. Tulving (1983) suggested that cues help retrieval if the same cues are present at encoding and at retrieval (encoding specificity principle). The closer the retrieval cue is to the original the better the cue works.

Some cues have meaningful links to the memories. Whereas some have no meaningful link.

Context-dependent forgetting is when memory retrieval is dependent on an external cue.

State-dependent forgetting is when memory retrieval is dependent on an internal cue.

AIM                         To investigate the effect of external context on recall

PROCEDURE     Deep-sea divers learned word lists and were later asked to recall them. The cues used were the contexts where learning took place. Group 1 learned and recalled the list on land; group 2 learned the list on land and recalled the list underwater. Group 3 learned the list underwater and recalled it on land; group 4 learned and recalled the list underwater.

FINDINGS      When the external contexts of learning and recall were different accurate recall was 40% lower than when the external contexts matched.

CONCLUSION   When the external cues available at learning were different to the ones at recall it lead to retrieval failure due to lak of cues.

Supporting evidence - Studies such as Godden and Baddeley's with deep sea divers support the theory. Eysenck (2010) suggested that retrieval failure is the main reason for forgetting in the long term memory - High validity

Everyday applications - An example of this would be someone that is upstairs in their house going downstairs to get something but forgetting what when they get there, they remember again when they go back upstairs. The application is that when people have trouble remembering something revisiting the environment where it was first experienced may help - High reliability

Context effects are not strong in real life - Baddeley (1966) suggested that different contexts have to be very different before an effect is seen. Learning something in one room and recalling it in another is unlikely to result in much forgetting because the environments are not different enough. This means that real-life applications of retrieval failure due to contextual cues don't actually explain much forgetting - Lacks external validity

Contexts effects only occurs when memory is tested in certain ways - Godden and Baddeley (1980) replicated their underwater experiment and used a recognition test instead of recall. There was no context-dependent effect; performance was the same in all four conditions. This limits retrieval failure as an explanation for forgetting because the presence or absence of cues only affects memory when you recall rather than recognition

Encoding specificity principle cannot be tested - When cues produce successful recall of a word it is assumed the cue was present at the time of learning and if a cue is unsuccessful it is assumed it was not present at the time of learning. There is no way to tell for certain whether a cue has been encoded or not