Menu

Coding, capacity and duration of MSM

Multistore Model of Memory

Long Term Memory

Working Memory Model

Forgetting: Interference theory

Forgetting: Retrieval failure

EWT: Misleading info (misleading questions and post event discussion)

EWT: Anxiety

EWT: Cognitive interview

Coding, Capacity & Duration of MSM

Coding AO1
Coding is the way in which information is processed and stored into memory e.g. acoustic, visual, semantic coding.

STM & LTM
Baddeley (1966) Acoustically, semantically similar study

Procedure: Participants were asked to recall a list of acoustically or semantically, similar or dissimilar words. They had to recall either immediately (to test STM) or after a 20 min delay (to test LTM).

Findings: Immediate recall was worse for acoustically similar words, indicating that STM primarily relies on acoustic coding, as the similarity in sounds interfered with word storage. Delayed recall was worse for semantically similar words, suggesting that LTM relies on semantic coding, as the similarity in meaning disrupted the storage process.

Capacity AO1
Capacity is the amount of information that the memory system can hold.

STM
Jacobs (1887) Digit span study

Procedure: Jacobs asked ppts to complete the digit span task. This involves participants immediately recalling a sequence of numbers in the correct order, with the sequence length increasing after each correct response to measure memory capacity.

Findings: Ppts could recall on average 9.3 numbers and 7.3 letters.

Miller (1956) Magic Number study

Procedure: Literature review of capacity of STM e.g. music notes, days of week etc.

Findings: Miller found the ‘Magic Number’ of average number of items recalled to be 7+/-2. He found this can be increased through chunking – grouping information into meaningful units.

Duration AO1
Duration refers to the length of time information can be held in that memory system.

STM
Peterson & Peterson (1959) Consonant trigram study

Procedure: Ppts were asked to recall consonant trigrams e.g. TRX519 after counting backwards in 3s or 4s. The IV was time in seconds (3, 6, 9, 12, 15, 18).

Findings: After 3 secs average recall was 80%. After 18 secs average recall was less than 10%.

LTM
Bahrick et al (1975) Yearbook study

Procedure: 392 ppts aged 17-74 years from USA. They had a recognition test (50 photos from high school yearbooks) and a free recall test (recall names from graduating class).

Findings: Recognition test: 15yrs 90% / 48yrs 70%. Free recall test: 15yrs 60% / 48yrs 30%.

AO3

+/- Methodological issues: Internal & ecological validity

- P&P measuring displacement instead of trace decay - low construct validity

- Individual differences (age)

- Miller overestimated capacity - closer to 4 (Cowan, 2001)

You can purchase fully written out, A* quality AO3 paragraphs from the resources page.

Back to menu

Forgetting: Retrieval Failure

AO1​​

Retrieval failure is where information is available but cannot be recalled because of the absence of appropriate cues.

Tulving (1983) proposed the encoding specificity principle, suggesting that the same cues need to be present at the time of encoding and retrieval for recall to be most successful. If cues are different at these times, there will be some forgetting.

There are two types of retrieval failure:

• Context dependent forgetting: this suggests that if the external environmental cues are different at the time of encoding and recall there will be some forgetting.

• State dependent forgetting: this suggests that if the internal emotional cues are different at the time of encoding and recall there will be some forgetting.

​

Context dependent forgetting

Godden and Baddeley (1975) Diver study

Procedure: Participants were asked to learn a list of words on land or sea. They were then asked to recall the words on land or sea, creating four conditions.

Findings: Accurate recall was 40% lower in the mismatched environments compared to when the recall was in the same environment. It was concluded that the retrieval failure was due to an absence of environmental, context dependent cues at the time of recall.

​

State dependent forgetting

Carter & Cassaday (1998) Antihistamine study

Procedure: Participants were asked to learn a list when they had taken an antihistamine (making them drowsy) or with no drug. They were then asked to recall the words when they had taken an antihistamine or with no drug, creating four conditions.

Findings: Accurate recall was worse in the mismatched emotional states compared to when the recall was in the same emotional state. It was concluded that the retrieval failure was due to an absence of state dependent cues at the time of recall.​

​​

​​​​ AO3

+ Real world application to students learning information for exams

- Methodological limitations: the tasks lack mundane realism and the results of the studies lack ecologically validity

- Cannot test the ESP as it cannot be ensured that a specific cue was encoded or not. Leads to a circular argument. 

- Reliable finding that is found consistently in lab studies and in real world scenarios

​​

You can purchase fully written out, A* quality AO3 paragraphs from the resources page.

​

Back to menu

Eye-witness Testimony: Misleading Information

Eyewitness testimony is the account of someone who has seen or witnessed a crime. It is used in the criminal justice system to help convict offenders.

​

Misleading information is a key factor that can reduce the accuracy of eye witness testimony and is incorrect information given to an eyewitness after an event.

​

Leading questions

AO1​​

Loftus and Palmer (1974) Car crash study

Procedure: 45 participants watched a film clip of a car accident and what asked about how fast will the cars going when they verb each other. The IV was the intensity of the verb which included hit, contacted, bumped, collided or smashed.

Findings: The verb ‘contacted’ produced a mean estimate of 31.8mph and the verb ‘smashed’ produced a mean estimate of 40.5mph. This suggests that the leading question biased eyewitness recall, as the word smashed yielded a faster estimate than contacted.

There are two explanations as to why this occurred:

• Response bias explanation: Participants memory did not actually change but the leading question influenced the response they gave to the researcher.

• Substitution explanation: The wording of the question actually did affect the participants memory. This is supported by Loftus and Palmer’s follow up ‘broken glass’ experiment. More participants in the ‘smashed’ condition reported seeing broken glass when indeed there was not any.

Post event discussion

AO1​​

Gabbert et al (2003) Stolen purse study

Procedure: Participants were put in pairs, and they watched a video of the same crime but from different perspectives. They were then allowed to discuss what they had seen on the video before completing a recall test.

Findings: 71% of participants wrongly recalled aspects of an event they did not see. 60% of participants said that the girl was guilty even though they had not seen her commit a crime. In the control group where there was no discussion there were no errors.

There are two explanations as to why this happens:

• Memory conformity: This is when witnesses go along with each other to win social approval or because they believe the other witness is correct.

• Memory contamination: When co-witnesses disturb discuss a crime they mix information from the other person into their own memory.

​​

​​​​ AO3 (for both topics)

+ Real world application to criminal justice system

- The results from the lab studies have low ecologically validity. Higher anxiety in real life.

- Even when two leading questions were asked in the field experiment Yuille & Cutshall (1986) it had no effect on recall

- There are individual differences in the ability to recall accurately - age response bias

​​

You can purchase fully written out, A* quality AO3 paragraphs from the resources page.

​

Back to menu