Forgetting

What are the two theories of forgetting?

1. Interference theory:

• Retroactive interference

• Proactive interference

2. Retrieval failure:

• State dependent forgetting

• Context dependent forgetting

Outline the interference theory

When 2 pieces of (usually similar) information get confused with each other resulting in the memories being distorted/alerted.

Outline proactive interference.

• Old information disrupts new information

• Interference works forward in time, when old information already stored interferes with recalling something new

• Pro = previous

Outline retroactive interference.

• New information disrupts old information

• interference works backwards in time, new information being stored interferes with recall of old information

• Re = recent

Outline retrieval failure theory.

• An accessibility theory which explains forgetting information from the LTM

• Tulving proposed that information is stored in memory but we have a problem with retrieving it (accessing it)

• When we store a new memory, we also store information that occurred around it

- e.g. feelings, place, weather etc.

• Known as retrieval cues, these help us access memories

What are the two types of retrieval cues?

1. Context dependent cues:

• External environment e.g. smell, sound, place etc.

• So being in a different environment would inhibit memory as we would lack environmental cues

2. State dependent cues:

• Emotional/psychological state e.g. mood, emotion, drunk etc.

• So being in a different emotional state would inhibit memory as we would lack state dependent cues

What is cue dependency?

• Encoding specificity principle developed by Tulving

• The greater the similarity between the coding & retrieval event, the greater the likelihood of recalling the original memory

• i.e. forgetting in LTM happens due to absence at recall of appropriate cues/prompts that was encoded 

Outline Keppel & Underwood 1962 in terms of supporting proactive interference.

PROCEDURE:

• Lab experiment, repeated measures design

• Participants had to recall 3 letter trigrams (e.g. ADH) after different intervals (3,6,9 seconds etc.)

• To prevent rehearsal, participants had to count backwards in 3 seconds before recalling

RESULTS:

• Participants remembered the trigrams present first despite interval length, found it harder to recall later trigrams

CONCLUSION:

• Proactive interference had occurred as memory from earlier trigrams (which transferred to LTM) interfered with memory for new consonant because of similarity of information

Outline Schmidt et al 2000 in terms of supporting retroactive interference. 

PROCEDURE: 

• Field experiment

• Former school students given a map of school area & all 48 street names were replaced with numbers

• Asked to recall as many old street names as possible in a questionnaire

• Questionnaire also asked how many times they moved, where they lived, how long etc.

RESULTS:

• Positive correlation between number of times participants had moved house outside school area & number of street names they’d forgot 

CONCLUSION:

• Learning new street names when moving houses makes recalling old street names harder 

Outline the MchGeoch & McDonald (1931) study in terms of effects of similarity: Retroactive interference.

PROCEDURE:

• Participants given a list of 10 adjectives to learn until they felt confident they could recall it 100% accurately

• After a 10 minute rest, participants learnt a list of 3 digit numbers, lists of unrelated words, nonsense syllables, synonyms of the 1st list etc.

RESULTS:

• New lists interfered with original list of 10 words participants knew by heart

• The synonym list affected the recall of the original list the most, worst recall produced

CONCLUSION:

• Supports retroactive interference

• Interference is stronger when the degree of similarity between items is greater

Outline Baddeley & Hitch (1977) in terms of retroactive in the real world.

PROCEDURE:

• Field experiment, Quasi experiment

• Asked rugby players to recall the names of the teams they played with earlier in the season

1. Condition 1 = participants played every match in the season

2. Condition 2 = participants missed some games

RESULTS:

• Players who had played the most games forgot proportionally more names than those who played fewer games

CONCLUSION:

• The learning of new team names interfered with the memory of older team names supporting retroactive interference 

Outline Godden & Baddeley (1975) in terms of supporting context-dependent forgetting.

PROCEDURE:

• Divers had to learn/recall a list of words on land/water

1. Group 1 = Learn on land + Recall on land

2. Group 2 = Learn on land + Recall underwater

3. Group 3 = Learn underwater + Recall on land

4. Group 4 = Learn underwater + Recall underwater

RESULTS:

• Accurate recall was 40% lower in the non-matching conditions than the matching conditions

CONCLUSION:

• Recall was worse in non-matching because of encoding specificity principle (ESP), environment was different from event on coding & recall so external cues were absent making recall worse

Outline Carter & Cassaday (1998) in terms of supporting state-dependent forgetting.

PROCEDURE:

• Gave some participants sedatives (antihistamine) making them slightly drowsy (changed the ppnts normal physical condition (by making them drowsy) to test whether that internal state acts as a cue for memory)

• Participants had to learn & recall a list of words & prose passages

1. Learn on drugs + Recall on drugs

2. Learn on drugs + Recall not on drugs

3. Learn not on drugs + Recall on drugs

4. Learn not on drugs + Recall not on drugs

RESULTS & CONCLUSION:

• Conditions where internal state was mismatched performance on memory test was significantly worse

• So when internal cues are absent there’s more forgetting

Outline Tulving & Psota (1971) in terms of ‘interference or cue-dependent forgetting’.

PROCEDURE:

• Lab experiment, repeated measures design

• Participants given 6 different word lists to remember, each list was divided into 6 categories (so over the 6 lists, there were 36 categories)

1. Free Recall:

- After each list presented, participants had to free recall as many words as possible

- Then there was a final total free recall (all lists)

1. Cued Recall (same participants):

- Participants given category names (the cue) & asked to recall all the words from the list, some participants only learned 1 list, some learned 1&2 etc.

RESULTS:

• The more lists the participants had to learn, the worse the free recall = supporting retroactive interference

• When participant given cued recall interference effects disappeared (remembered 70% of words)

CONCLUSION:

• Interference doe cause forgetting but only when the stimulus is faced with multiple responses/free recall

• Presence/Absence of cues has a greater impact on recall than interference (cue dependent forgetting)

What are the strengths of interference as an explanation for getting?

Real world interference:

• Baddeley & Hitch rugby experiment shows interference has an effect in everyday situations

Schmidt et al:

• Field experiment, high in ecological validity & mundane realism so more generalisable to real world

• Lots of empirical (factual) evidence 

What is a weakness of interference as an explanation for getting?

Effects of interference disappear when faced with cues showing that interference only causes forgetting when stimulus is doing free recall:

• Supported by Tulving & Psota exp 1971

Interference is a partial explanation for forgetting:

• Conditions needed for interference forgetting is rare, much of the evidence is lab based, so researcher can create ideal conditions for interference

- E.g. 2 memories usually have to be similar to interfere with each other, doesn’t happen very often (it could but not a lot)

• So forgetting is better explained by other theories

What are the strengths of retrieval failure?

Has supporting empirical evidence:

• Godden & Baddeley, Carter & Cassedey

Real world applications:

• It’s found that if students are tested in the same room they were taught, by the same teacher their exam performance improves

• Also just thinking about the room where you did the original learning (mental reinstatement) is as effective as the said above

What are the weaknesses of retrieval failure?

Context-dependent cues aren’t strong:

• Baddeley argues contexts must be very different to have an effect, it’s hard to find an environment as different as land & water

• Learning in one room & recalling in another wouldn’t have much of an effect, not different = theory less valid, not applicable to everyday life

Recall versus recognition:

• Godden & Baddeley replicated their underwater experiment but replaced recall with recognition

• Contexts effects had disappeared, suggesting context dependent forgetting is limited as it doesn’t affect all types of memory

• Theory less valid