explanations for forgetting

• interference theory

  interference is forgetting because of one memory blocking another causing one or both to be distorted or forgotten, there are two types of interference:

  proactive interference - occurs when older memories, already stored, disrupt the recall of newer memories e.g. a teacher cant remember the names of new student due to past students

  retroactive interference - occurs when newer memories disrupt the recall of older memories already stored e.g. teacher cant remember old students names because of the new students

  the degree of forgetting is greater when memories are similar
• research on effects of similarity

  McGeoch and McDonald (1931) studied retroactive interference by changing the amount of similarity between two sets of materials, participants had to learn a list of 10 words until they could remember them and then six groups each learned a new different list:

  group 1 - synonyms, same meaning as the original

  group 2 - antonyms, opposite meanings to the original

  group 3 - unrelated words to the original

  group 4 - consonant syllables

  group 5 - three-digit numbers

  group 6 - no new list (control group)
• research on effects of similarity results

  when the participants were asked to recall the original list of words, the most similar material (synonyms) produced the worst recall, this shows that interference is strongest when the memories are similar
• interference evaluation strengths

  real world interference - interference effects in more everyday situations, Baddeley and Hitch (1977) asked rugby players to name the teams they have played against, players who played the most games had the worst recall showing that interference can operate in at least some real world situations increasing validity of the theory
• interference evaluation limitations

  interference is temporary and can be overcome by using cues, Tulving and Psotka (1971) gave participants multiple list of words to learn, split into categories, recall 70% for the first list but became progressively worse when additional lists were added, however when they were told the categories recall rose to about 70% again
• retrieval failure theory 


  retrieval failure is a form forgetting which occurs when we don't have the necessary cues (a 'trigger' of information) to access memory, the memory is available just not accessible unless a suitable cue is provided
• encoding specific principle

  Tulving (1983) found a pattern to the findings, stating that a cue has to be: present at encoding - when we learn material and present when recalling it

  there are examples of non-meaningful cues: context dependent cues - external cue such ad weather or place and state dependent cues - feeling upset or drunk
• research on context dependent forgetting

  Baddeley (1975) studies deep sea divers who work underwater to see if training on land helped or hindered their work underwater when learning a list of words and created four conditions:

  learn on land - recall on land

  learn on land - recall underwater

  learn underwater - recall on land

  learn underwater - recall underwater

  accurate recall was 40% lower in the non-matching conditions showing that external cues are useful
• research on state dependent forgetting

  Carter and Cassaday (1998) gave antihistamine drugs making participants slightly drowsy creating a different internal physiological state to learn a list of words and created four conditions:

  learn on drug - recall on drug

  learn on drug - recall when not on drug

  learn when not on drug - recall on drug

  learn when not on drug - recall when not on drug

  when there was a mismatch between internal state at learning and recall, performance on the memory test was significantly worse so when cues are absent there is more forgetting
• retrieval failure evaluation strengths

  retrieval cues can help overcome everyday situations such as walking into a room and forgetting what you need and walking out then remembering - context dependent forgetting
• retrieval failure evaluation limitations

  context effects may depend substantially on the type of memory being tested, Baddeley (1980) replicated the underwater test but used a recognition test, there was no context dependent effect, performance was the same in all four conditions suggesting that retrieval failure is a limited explanation