Multi-Store Model of Memory
The Multi-Store Model of Memory
The Multi-Store Model (MSM) was proposed by Atkinson and Shiffrin (1968). It describes memory as flowing through three separate stores, each with different characteristics.
The Three Stores
| Store | Duration | Capacity | Encoding |
|---|---|---|---|
| Sensory register | Less than 1 second | Very large — takes in all sensory information | Sense-specific (visual = iconic; auditory = echoic) |
| Short-term memory (STM) | Up to 30 seconds (without rehearsal) | 7 ± 2 items (Miller, 1956) | Mainly acoustic (sound-based) |
| Long-term memory (LTM) | Potentially unlimited duration | Potentially unlimited capacity | Mainly semantic (meaning-based) |
How the Model Works
1. Information from the environment enters the sensory register through the senses (sight, hearing, touch, taste, smell)
2. If attention is paid to the information, it moves into short-term memory
3. If the information is rehearsed (repeated), it transfers to long-term memory — this is called maintenance rehearsal
4. Information in LTM can be retrieved back into STM when needed
Key Studies Supporting the MSM
Baddeley (1966) — Encoding in STM and LTM:
- Participants confused acoustically similar words in STM tasks (e.g. "man", "mat", "map") — supporting acoustic encoding in STM
- Participants confused semantically similar words in LTM tasks (e.g. "big", "large", "huge") — supporting semantic encoding in LTM
- This shows STM and LTM are separate stores with different encoding methods
Case study of HM (Henry Molaison):
- After brain surgery to treat epilepsy, HM could no longer form new long-term memories but his STM was intact
- This supports the idea that STM and LTM are separate stores located in different brain areas
Strengths of the MSM
- Research support — studies like Baddeley (1966) and the case of HM provide evidence that STM and LTM are distinct stores
- Influential — it was the first cognitive model of memory and has generated a huge amount of research
- Clear and testable — the model makes specific predictions that can be tested experimentally
- Real-world application — understanding STM capacity (7 ± 2) has influenced design (e.g. phone numbers, chunking information)
Weaknesses of the MSM
- Oversimplified — it treats STM and LTM as single, unitary stores, but research shows there are different types of LTM (episodic, semantic, procedural — see next note) and different components of STM (Baddeley's Working Memory Model)
- Rehearsal is not always needed — some information enters LTM without rehearsal (e.g. flashbulb memories of dramatic events), suggesting rehearsal is not the only mechanism for transfer
- Too linear — the model suggests information flows in one direction, but in reality we use LTM knowledge to process information in STM (e.g. recognising a word requires accessing LTM)
- Maintenance rehearsal — Craik and Lockhart (1972) argued that elaborative rehearsal (thinking about meaning) is more important for LTM transfer than simple repetition
Exam Tips
- Draw the diagram — sensory register → (attention) → STM → (rehearsal) → LTM, with retrieval going back
- Always use key terms: encoding, duration, capacity, rehearsal, retrieval
- Cite Baddeley (1966) for encoding differences and Miller (1956) for STM capacity
- For AO3 evaluation, balance strengths and weaknesses — the model is supported but oversimplified
- A common 12-mark question: "Evaluate the multi-store model of memory" — use the PEEL structure (Point, Evidence, Explain, Link)