AQA Psychology A-Level: Memory

Part 1 — Coding, Capacity and Duration of Memory

  • Coding: Refers to the format of information stored in memory stores.

    • Short-term memory (STM) is primarily acoustic.
    • Long-term memory (LTM) is primarily semantic.
    • Research:
    • Baddeley (1966):
      • Found that recall of acoustically similar words produces more errors in STM.
      • Recall of semantically similar words produces more errors after 20 minutes in LTM.

  • Capacity: Amount of information a memory store can hold.

    • STM has a capacity of around 7 ext{ +/- } 2 items (Miller).
    • LTM has an unlimited capacity.
    • Chunking: Grouping information into chunks helps recall (e.g., remembering 7 days of the week).
    • Research:
    • Jacobs:
      • Mean letter span is 7.3; mean digit span is 9.3.

  • Duration: Length of time information is stored.

    • STM lasts for 18-30 seconds (Petersen et al., 1959).
    • LTM is considered to be unlimited (Bahrick et al., 1975):
    • Recall decreased from 90 ext{%} to 70 ext{%} over 15-46 years post-graduation.

  • Evaluations:

    • Strength of Bahrick et al.'s study: Uses meaningful stimuli leading to high ecological validity.
    • Limitations of Jacobs' study: Potential confounding variables (e.g., noise).
    • Some argue Miller overestimated STM capacity, suggesting more about 4 chunks rather than 5-9 items.

Part 2 — The Multi-Store Model of Memory (MSM)

  • Overview: MSM illustrates how memory is stored, transferred, retrieved, and forgotten.

  • Memory Stores:

    • 1. Sensory register
    • 2. Short-term memory (STM)
    • 3. Long-term memory (LTM)
    • Sensory Register: Has a sub-store for each sense, a large capacity, but only lasts <0.5 seconds; information must be attended to for further processing.

  • Short-term Memory (STM):

    • Encoding: Mainly acoustic (Baddeley).
    • Capacity: 7 ext{ +/- } 2 (Miller).
    • Duration: 18-30 seconds (Petersen).
    • Maintenance Rehearsal: Repeating information keeps it in STM; prolonged rehearsal helps transfer it to LTM.

  • Long-term Memory (LTM):

    • Encoding: Mostly semantic.
    • Capacity: Unlimited.
    • Duration: Very long (over 46 years, Bahrick et al.).

  • Retrieval: Involves transferring information back to STM from LTM for use.

  • Limitations:

    • Disagreement on whether STM is a single store.
    • Different types of LTM exist (i.e. procedural, semantic, episodic).
    • Research by Craik and Watkins (1973): Type of rehearsal (elaborative) may be key to transferring information to LTM, not merely the amount.

Part 3 — Types of Long-Term Memory

  • Types:

    • 1. Episodic Memory: Memories of personal significance (events) and contextual details (e.g., weddings).
    • 2. Semantic Memory: Knowledge about the world, meanings of concepts and words.
    • 3. Procedural Memory: Skills and actions learned unconsciously (e.g., riding a bike).

  • Differences:

    • Episodic and semantic must be recalled consciously; procedural is retrieved unconsciously.
    • Research:
    • Petersen et al. found different neurological bases for different types of LTM.
    • HM and Clive Wearing: One memory type can be impaired while others remain intact.

  • Practical Implications:

    • Understanding LTM types can improve treatment for cognitive impairments.

Part 4 — The Working Memory Model (WMM)

  • Components:

    • Central Executive: Processes and allocates tasks to other systems.
    • Phonological Loop: Handles auditory information and maintenance rehearsal.
    • Contains the articulatory process (stores heard words) and the phonological store.
    • Visuo-Spatial Sketchpad: Manages visual and spatial information, with a capacity of about 4-5 chunks (Baddeley).
    • Episodic Buffer: Integrates information from all stores; links STM to LTM.

  • Strengths:

    • Research, such as Shallice and Warrington’s study on KF, supports the model.
    • Neuroimaging (Braver et al.) shows that cognitive load correlates with increased activation in the prefrontal cortex.

  • Limitations:

    • Central Executive definition lacks clarity; may comprise multiple components.

Part 5 — Explanations for Forgetting: Interference

  • Interference: A recall block caused by competing memories; can be retroactive (new memories affect old) or proactive (old memories affect new).

    • Example: McGeoch and McDonald (1931) demonstrated retroactive interference with different word lists.

  • Critique:

    • Lack of ecological validity in lab studies due to the use of artificial stimuli.

  • Support:

    • Validity enhanced by lab conditions that control extraneous variables.

  • Further Evidence:

    • Baddeley and Hitch: Importance of interference in recall of rugby players.

Part 6 — Explanations for Forgetting: Retrieval Failure

  • Definition: Forgetting occurs when cues present during encoding are absent during retrieval (Tulving's Encoding Specificity Principle).

  • Types:

    • Context-dependent: External environment cues mismatch (e.g., Godden and Baddeley study).
    • State-dependent: Internal state cues mismatch (e.g., Carter and Cassaday study).

  • Implications:

    • Suggests cues can be powerful facilitators of recall.

  • Limitations:

    • Ecological validity concerns over extremes of context match in studies.

Part 7 — Misleading Information and Eyewitness Testimony

  • Eyewitness Testimony (EWT): Accounts by witnesses might be skewed by misleading information (leading questions).

  • Leading Question Study: Loftus and Palmer (1974): Showed effect of wording on speed estimates and memory recall.

  • Post-Event Discussions: Gabbert et al. (2003): Found high rates of inaccuracies due to discussions between witnesses.

  • Critiques:

    • Issues of own-age bias and demand characteristics presenting challenges for reliability and validity.

  • EWT Limitations:

    • Primarily artificial settings yield low ecological validity; real-life stress may impact accuracy differently.

Part 8 — Anxiety and EWT

  • Effect of Anxiety: Can enhance or impair the accuracy of EWT.

    • Negative Effects: Johnson and Scott (1976) showed reduced accuracy with high perceived threat.
    • Positive Effects: Yuille and Cutshall (1986) found high accuracy under real-life conditions of high anxiety.

  • Theoretical Models: Yerkes-Dodson Law emphasizes optimal arousal levels for improved performance but may oversimplify the complexity of anxiety's effects.

  • Ethical Considerations: Ethical issues arise when researchers expose participants to distressing situations.

Part 9 — Cognitive Interviews to Improve EWT Accuracy

  • Cognitive Interview Method:

    • Report Everything
    • Reinstate Context
    • Change Perspective
    • Reverse Order

  • Enhanced Cognitive Interview: Developed by Fisher et al., incorporating social strategies to foster better recall.

  • Challenges: Practical application difficulties due to time demands and training needs.

  • Research Findings: Mixed results in terms of increased inaccuracies alongside correct recall (Kohnken et al.).

    • Milne and Bull (2002): Certain CI steps yield greater recall accuracy than others.