Explanations of Forgetting – Interference

Question 1

What is forgetting

Answer 1

Forgetting refers to the inability to access or recover information that has been previously stored in memory. When you forget something, it means that it is inaccessible at the time of the attempted retrieval.

Question 2

What are the two main explanations of forgetting

Answer 2

1. Interference including proactive and retroactive interference;
2. Retrieval failure due to absence of cues

Question 3

Interference theory

Answer 3

Forgetting occurs in LTM because two memories are in conflict. This might result in the forgetting or distorting of one memory or the other memory or both memories. This is more likely to happen if the memories are similar. There are two types of interference – proactive interference and retroactive interference.

Question 4

What is positive interference

Answer 4

When an old memory interferes/disrupts with the recall of a new memory .e.g. a teacher struggling to learn the names of students in her new class because she’s confusing the names with students in her old class

Question 5

Retroactive interference

Answer 5

When a new memory interferes/disrupts with an old memory e.g. a teacher forgetting the names of students in the old class after learning the names of students in the current class.

Question 6

Why is interference worse when memory are similar

Answer 6

1) In PI previously stored information makes new information more difficult to store.
2) In RI new information overwrites previous memories which are similar.

Question 7

Explain interference experiment

Answer 7

McGeoch and McDonald (1931)
Aim: to see if interference had an impact on forgetting

Method:
Task 1 – Six groups of Participants had to learn list of words until 100% accurate.
Task 2 – Five groups of participants had to learn a new list. (this was the interference task) The words in the new lists varied in terms of how similar they were to the original list:

Group 1 – Synonyms (words with same meaning)
Group 2 - Antonyms (words with opposite meaning)
Group 3 - Unrelated words
Group 4 - Nonsense syllables
Group 5 - 3-digit numbers
Group 6 - No new list (control condition)

Task 3 – all pps were then required to recall the first original list learned in Task 1

Question 8

Results of McGeoch and McDonald

Answer 8

As can be seen from the bar chart above, the control group recalled the most number of words as they had no interference task.

However, for those participants who were given an interference task (another list to learn), those who had to learn numbers did best in recalling the original list of words presumably because numbers do not interfere with words. However the group who were given the list of synonyms for their interference task had the lowest recall score from the original list – this can be explained by the fact that interference occurred because the original list of words had a similar meaning to the second list of words – and as it has been shown that interference is most likely to occur when two pieces of information are similar, this study supports this notion.

Question 9

Strengths of interference

Answer 9

1. One strength of the Interference explanation of forgetting is that it is supported by many controlled lab studies which have shown that both types of interference lead to information in LTM being forgotten. For example McGeoch and McDonald’s study supported the interference theory. Also as lab studies are well-controlled, extraneous variables are minimized. For example, in McGeoch and McDonald’s study all lists given to participants would have been standardized and matched on levels of difficulty reducing the extraneous variable of lists being too hard or too easy.
   This supports idea that interference is a valid explanation of forgetting.
2. Another strength of interference theory is that some realistic studies have been conducted .e.g. Baddeley and Hitch (1977) that support the idea that interference does occur in everyday settings.

Question 10

Explain baddeley and hitch interference experiment

Answer 10

Baddely and Hitch 1977

AIM: wanted to investigate interference in everyday life

start to the end of the season was the same for all players, and players were asked to recall the names of the teams they had played against earlier in the season.

METHOD:The sample comprised rugby union players who had played every match in the season and players who had missed some games due to injury. The length of time from the

Question 11

Baddeley and hitch interference experiment results and conclusion

Answer 11

RESULTS:
The findings showed that the players who had played the most games forgot proportionately more games than those who had played fewer games due to injury.
In fact, accurate recall of teams they has played did not depend on how long ago they had last played a match- they were equally accurate recalling the last team they had played whether or not it was a few days ago or 3 weeks ago.

Conclusion:
Baddeley and Hitch concluded that this was the result of retroactive inference, as the memory of new information (new team names) interfered with the memory of old information (earlier team names).

Question 12

Weakness of interference

Answer 12

1. One limitation of the interference explanation of forgetting is that most supporting evidence which is gathered from lab studies, use unrealistic material (normally lists of words). In real life, we rarely remember lists of random words. Thus studies supporting interference lack ecological validity which the causes problems in applying interference to everyday life.
2. Another limitation of Interference research is that in lab experiments the time period between learning lists of words and recalling them tends to be short .e.g. 20 minutes. In real life there tends to be much longer gaps between when we learn new information. Therefore supporting research may lack validity and not reflect how interference works in real life. Therefore the role of interference in forgetting as shown by lab studies may be exaggerated.
3. Yet another limitation of interference as an explanation of forgetting is the fact that research has shown that the effects of interference can be overcome using cues. In support of this notion, Tulving and Psotka (1971) gave participants 5 lists of 24 words organized into categories. It was found that recall was about 70% for the first list and this accuracy decreased as the lists went on. This was due to interference (since participants starting to confuse the lists). However when participants were reminded of each category that the word list belonged to (.i.e. given a cue) recall accuracy improved- to about 70% again. This suggest that memories of the words were stored in the LTM, but that cues were needed to access some of these words. This study therefore shows that interference can be overcome so may not be a strong theory of forgetting in LTM.