Explanations for forgetting - Memory Psychology

Interference theory:
Interference is…forgetting because one memory blocks another, causing one or both memories to be distorted or forgotten. This is even more likely when the two memories are similar (eg. simultaneously learning 2 languages (Chandler (1989)).

Proactive Interference: an older memory interferes with a new one (eg. calling your new boyfriend, your old boyfriends’ name)

Retroactive Interference: a newer memory interferes with an older one (eg. your teacher has learnt so many new names this year that they struggle to remember previous students’ names).

Underwood and Postman (1960):

AIM – to see if new learning interferes with previous learning

METHOD – Participants were divided into two conditions: one was asked to learn a list of word-pairs (eg. cat-tree), and the other was asked to learn the same set of words, but also a second set which had the same stimulus word, but a different response word (eg. cat-stone). Both groups were asked to recall the first list of word pairs.

RESULTS – the control condition (one list of words) recalled the pairs more accurately than the experimental condition.

CONCLUSION – this suggests that by learning the second set of word-pairs, it interfered with the participants’ ability to recall the first list – this is an example of retroactive interference.

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 words until they could remember them 100% accurately. They were then asked to learn a new list.

There were 6 conditions, and each condition had a different type of list to learn:

1.     synonyms

2.     antonyms

3.     words unrelated to the original ones

4.     non-sense syllables

5.     3-digit numbers

6.     no new list

FINDINGS: when participants recalled the original list of words, their performance depended on the nature of the second list. The most similar material (synonyms) produced the worst recall – showing interference is strongest when the memories are similar.

EVALUATION:

P: research to support this theory all use laboratory experiments

E: participants are given artificial tasks eg. leaning lists of word-pairs (Underwood and Postman, 1960).

E: this means the research may lack ecological validity and therefore it would be unsuitable to generalise findings to forgetting in real life.

P: in an experiment, the time between learning and remembering is short

E: for example, a participant may have to learn a list of 20 words – then recall them 20 minutes later

E: we don’t normally learn in an artificial way like this and so it would be unsuitable to generalise the findings to real life scenarios.

P: there is research support

E: for example, Underwood and Postman (1960) found that by learning a second set of word pairs, it interfered with a participants’ ability to recall the first set

E: this is an example of retroactive interference and therefore adds to the credibility of this theory

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Retrieval Failure:
Retrieval Failure is when the information is stored in LTM but cannot be accessed. Forgetting is due to a lack of retrieval cues.

Tulving (1973) developed the Encoding Specificity Principle (ESP) which stated that the greater the similarity between the encoding event (remembering) and the retrieval event (recalling), the greater the likelihood of recalling the original memory. If we cannot recall information, it may be because we’re not in a similar situation to when the memory was stored.

Context-dependent forgetting is an external cue (we encode information with context) and occurs when the environment during recall differs from the environment we were in when we were learning.

SUPPORTING RESEARCH: Godden and Baddeley (1975)

Participants heard lists of eithers either on the beach (dry condition) or underwater (wet condition). They were then tested on their recall in either the same condition they learnt in, or the alternative environment. Significantly more words were recalled when they were in the same conditions which demonstrates that context helps retrieval, therefore providing support for context-dependant forgetting.

State-dependent forgetting is an internal cue (we encode information with our mental state, eg. how we are feeling) and occurs when our mood or physiological state during recall is different from our mood/state when learning.

SUPPORTING RESEARCH: Goodwin et al (1969)

Some participants were tested whilst either: sober on both days, intoxicated both days, or sober one day and intoxicated the other. More recall errors were made by those not in the same physiological state (ie. sober one day, intoxicated the other) which demonstrates that internal cues can aid recall – suggesting state-dependant forgetting is a valid explanation for forgetting.

EVALUATION:

P: There are a lot of supporting studies

E: For example, the study by Godden and Baddeley (1975) which found that participants’ memory was better when recalling words in the same environment they learnt them in, and Goodwin et al (1969) who found that less errors on a recall test when the participant was in the same physiological state in both conditions

E: This vast amount of supporting evidence increases the validity and credibility of an explanation

P: Context-effects need to be questioned

E: Baddeley (1997) believes that context effects in real life aren’t strong enough to result in forgetting

E: This means that retrieval failure due to contextual cues can’t really explain every-day forgetting and therefore lacks real life application since context needs to be extremely different before an effect is seen.

P: The Encoding Specificity Principle cannot be tested

E: In an experiment where a cue produces the successful recall of a word, we assume that the cue must’ve been encoded at the time of learning – if unsuccessful, we assume the cue wasn’t encoded

E: However, there is no way to test this and therefore it’s based purely off assumptions – thus, validity needs to be questioned.