MEM 08 - Forgetting Interference Flashcards
What is interference?
Forgetting (in LTM) because one memory disrupts another, causing one or both memories to be distorted or forgotten
What are the two types of interference?
Proactive and retroactive interference
What is proactive interference
- Forgetting occurs when older memories disrupt the recall of newer memories (pro meaning working forwards, from old to new)
- The degree of forgetting is greater when the memories are similar
What is retroactive interference?
- Forgetting occurs when newer memories disrupt the recall of older memories (retro meaning working backwards, from new to old)
- The degree of forgetting is greater when the memories are similar
Who conducted research on the effects of similarity?
McGeoch and McDonald
What was the procedure of the research on the effects of similarity?
- McGeoch and McDonald 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 with 100% accuracy
- They then learned a new list
There were six groups of participants who had to learn different types of new lists:
- Group 1: synonyms - words with the same meanings as the originals.
- Group 2: antonyms - words with the opposite meanings to the originals
- Group 3: words unrelated to the original ones
- Group 4: consonant syllables
- Group 5: three-digit numbers
- Group 6: no new list - these participants just rested (control condition)
What was the findings/conclusion of the research on the effects of similarity?
- 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
What was the explanation for the research on the effects of similarity?
- Forgetting could be due to PI – previously new information makes new similar information more difficult to learn
- Or due to RI – new information overwrites previous similar memories because of the similarity
What does the idea of interference suggest?
The idea interference suggests that information in long-term memory may become confused or combined with other information during encoding thus distorting or disrupting memories
What are the strengths of the theory of interference?
- There is evidence for interference effects in everyday situations
- One strength of the interference theory comes from the evidence of retrograde facilitation
What are the limitations of theory of interference?
- Inteference may cause some forgetting in everday situations, but it is unusual
- Inteference is temporart and can be overcome by using cues (hints or clues to help us remember something)
- Most supporting studies are lab-based`
What evidence is there for the effects of inteference in everyday situations?
- Alan Baddeley and Graham Hitch (1977) asked rugby players to recall the names of the teams they had played against during a rugby season
- The players all played for same time interval (over one season) but the number of intervening games varied because some players missed matches due to injuries
- Players who played the most games (most interference for memory) had the poorest recall
- This study shows that interference can operate in at least some real-world situations, increasing the ecological validity of the theory
What evidence is there of retrograde facilitation?
- Anton Coenen and Gilles van Luijtelaar (1997) gave participants a list of words and later asked them to recall the list, assuming the intervening experiences would act as interference.
- They found that when a list of words was learned under the influence of the drug diazepam, recall one week later was poor (compared to the placebo-controlled group)
- But when a list was learned before the drug was taken, later recall was better than placebo.
- So, the drug actually improved (facilitated) recall of material learned beforehand.
- John Wixted (2004) suggest that the drug prevents new information (i.e. experience after taking the drug) reaching part of the brain involved in memories, so it cannot interfere retroactively (new experiences affecting the list of words) with information already stored
- This finding shows that forgetting can be due to interference -> reduce the interference and you reduce the forgetting
What evidence is there that interference can be overcome?
- Endel Tulving and Joseph Psotka (1971) gave participants a list of words organised into categories one list at a time (participants were not told what the categories were).
- Recall averaged about 70% for the first list, but became progressively worse as participants learned each additional list (proactive interference)
- At the end of the procedure participants were given a cued recall test (they were told the names of the categories) and recall increased back to 70%
- This shows that interference causes temporary loss of accessibility to material that is still in LTM, a finding not predicted by the interference theory decreasing its credibility
What is the issue with studies that support interference?
- Most studies supporting interference theory are lab-based, so researchers can control variables (e.g. the time between learning the material and recalling it)
- Control over confounding variables also means studies show a clear link between interference and forgetting
- But these studies use artificial materials and unrealistic procedures
- In everyday life we often learn something and recall it much later
