Cognitive psychology: the multi-store model, the working memory model, the reconstructive nature of memory, theories of forgetting, and key cognitive studies.

What this dot point is asking

Edexcel wants you to describe and evaluate the multi-store model and the working memory model, explain the reconstructive nature of memory, account for forgetting through competing theories, and use the named cognitive studies as evidence. The cognitive approach assumes that internal mental processes can be studied scientifically and that the mind works like an information processor, taking input, encoding and storing it, and retrieving output.

The answer

The multi-store model (Atkinson and Shiffrin, 1968)

Information from the environment first enters the sensory register, which is modality-specific (iconic for vision, echoic for sound), has a large capacity but a duration of only fractions of a second. If the person pays attention, the information passes to short-term memory (STM). STM holds about $7 \pm 2$ items (Miller's magic number), codes acoustically, and lasts up to about 18 to 30 seconds unless rehearsed. Maintenance rehearsal keeps material in STM and, with enough repetition, transfers it to long-term memory (LTM), which is potentially unlimited in capacity and duration and codes information semantically (by meaning). Retrieval brings material from LTM back into STM for use.

Supporting evidence includes the serial position effect (Glanzer and Cunitz, 1966): in free recall, the first words (primacy) and last words (recency) are recalled best. Primacy is explained by rehearsal into LTM and recency by items still sitting in STM, which supports separate stores.

The working memory model (Baddeley and Hitch, 1974)

The WMM is supported by dual-task studies: people struggle to do two tasks that use the same slave system (two visual tasks) but can do two tasks using different systems (one visual, one verbal) with little interference, showing the components are separate. The case of patient KF (Shallice and Warrington, 1970), whose verbal STM was severely impaired after brain damage while his visual STM was intact, shows STM is not a single store, which the MSM cannot explain.

The reconstructive nature of memory (Bartlett, 1932)

In Bartlett's War of the Ghosts study, English participants read an unfamiliar Native American folk tale, then recalled it after delays. Recall became shorter, more conventional and distorted to fit Western schemas (for example "canoes" became "boats" and supernatural elements were dropped). Bartlett concluded that memory is not a literal recording but a reconstruction guided by schemas, a foundation for later eyewitness testimony research (Loftus).

Theories of forgetting

Forgetting is explained by competing theories that Edexcel expects you to distinguish:

• Trace decay. The physical memory trace fades over time if not rehearsed, especially in STM.
• Interference. Other learning disrupts a memory. Proactive interference is when old learning blocks new learning (an old phone number intrudes on a new one). Retroactive interference is when new learning blocks recall of old learning. Interference is strongest when the two sets of material are similar (McGeoch and McDonald, 1931).
• Retrieval failure (cue-dependent forgetting). The memory is stored but inaccessible because the cues present at encoding are absent at recall. Tulving's encoding specificity principle covers context-dependent forgetting (external cues, such as Godden and Baddeley's divers recalling better on land or underwater matching learning conditions) and state-dependent forgetting (internal cues, such as mood).

Evaluation (GRAVE)

• Generalisability. Many memory studies use student samples and artificial word lists, limiting generalisation to everyday memory.
• Reliability. Laboratory memory studies are standardised and replicable, giving high reliability (the serial position effect replicates consistently).
• Application. The WMM informs dyslexia support and dual-task limits in driving; reconstructive memory underpins the cognitive interview used by police.
• Validity. Artificial materials (nonsense syllables, word lists) lack ecological validity; Bartlett's procedure lacked standardised instructions, lowering internal validity.
• Ethics. Memory studies are generally low-risk, though deception about the true aim is sometimes used and must be debriefed.

Examples in context

Example 1. Baddeley (1966) coding in STM and LTM. Baddeley gave participants lists of words that were either acoustically similar (cat, cab, can), acoustically dissimilar, semantically similar (big, large, huge) or semantically dissimilar. When recalling immediately (STM), participants made more errors with acoustically similar words, showing STM codes acoustically. When recalling after 20 minutes (LTM), they made more errors with semantically similar words, showing LTM codes semantically. This experimental support is central to the multi-store model and is a named Edexcel cognitive study.

Example 2. Godden and Baddeley (1975) context-dependent forgetting. Deep-sea divers learned word lists either on land or underwater, then recalled them in the same or a different environment. Recall was about 40 per cent better when the learning and recall environments matched. This is strong evidence for retrieval failure: the external context acts as a cue, and when cues at recall do not match those at encoding, forgetting occurs. It has a real application in the cognitive interview, where witnesses mentally reinstate the context of a crime to improve recall.

Try this

Q1. Describe the working memory model of memory. [4 marks]

• Cue. A central executive directs attention and controls the phonological loop (sound), the visuo-spatial sketchpad (vision and space) and the episodic buffer (integrating information and linking to LTM).

Q2. Explain retrieval failure as an explanation of forgetting. [3 marks]

• Cue. The memory is stored but inaccessible because the cues present at encoding (context or state) are absent at recall, so cue-dependent forgetting occurs, as shown by Godden and Baddeley's divers.

Q3. Evaluate the reconstructive theory of memory using one named study. [6 marks]

• Cue. Use Bartlett's War of the Ghosts (schemas distort recall) as support; weigh strengths (real application to eyewitness testimony) against weaknesses (lacked standardised procedure, lowering internal validity).