A comparison question is not two descriptions stapled together. It asks what each model can do that the other cannot — and the honest answer is that they are not even trying to explain the same thing.
📘 What you need to know
Both are cognitive models that conceptualise memory, and both give detail on capacity and duration.
The MSM covers all three stores; the WMM covers STM only. That difference explains most of the others.
The MSM treats memory as unitary stores; the WMM treats it as a dynamic, flexible process.
The MSM includes a rehearsal loop for moving information to LTM; the WMM is vague about LTM.
The WMM can explain parallel processing through the VSS and PL. The MSM cannot.
Both are supported by lab experiments and by case studies of brain damage.
Both share the same weaknesses: lab tasks lack mundane realism, case studies lack generalisability.
Start with what each one covers
Open a comparison answer with this point and everything else follows from it. Criticising the WMM for ignoring LTM is like criticising a street map for not showing the whole country.
If you only remember one thing for a comparison question, remember these two shapes. Linear versus parallel is the difference every other point hangs off.
Similarities
Both conceptualise memory — they are both cognitive models rather than descriptions of brain anatomy.
Both give detail on the capacity and duration of each store or component.
Both are supported by lab experiments (Glanzer & Cunitz; Baddeley) and by case studies of brain-damaged patients such as HM and KF.
Both inherit the same weaknesses: lab research lacks mundane realism because the tasks are artificial, and case studies lack generalisability because they rest on one participant.
Neither has ever had its central claims fully measured: the capacity and function of the CE and EB have never been measured, and nor has the exact duration and capacity of LTM.
Differences
Question
Multi-store model
Working memory model
What does it cover?
Sensory register, STM and LTM
STM only — the “here and now”
What is memory like?
A set of unitary stores
A dynamic, flexible process
How does information reach LTM?
Through a clear rehearsal loop
Vague — the episodic buffer is the only route
Can it explain doing two things at once?
No — a linear model has no mechanism for it
Yes — parallel processing via the VSS and PL
Which research supports it?
Serial position effect lab studies
Dual-task studies
What does it fail to explain?
How the stores actually operate; the different types of LTM
Anything beyond STM, including changes in processing ability with practice or time
A comparison answer that alternates — “the MSM does X, whereas the WMM does Y” — scores far higher than one that describes the MSM for a page and then the WMM for a page. Use “whereas” deliberately and often.
The fair verdict. Neither model wins outright. The MSM is broader but shallower; the WMM is narrower but far more detailed about the part it covers. Saying so is a stronger conclusion than picking a favourite.
Link to concepts
Perspective — the concept of working memory is very useful for understanding how people attend to the here and now, and it applies directly in educational and clinical settings, for example testing cognitive ability or possible deficits in attention and information processing. The MSM does not have such a direct application to other settings.
Bias — both models may lack cultural relativism, being biased towards Westernised rather than collectivist concepts of memory. Eastern collectivist cultures tend to focus on contextual information and group or social relationships in memory, which may not fit neatly into a box-and-arrow diagram. The cognitive approach also uses machine reductionism to depict human cognition, which may not align with cultures where the human element of a memory matters more than the processes that formed it.
Exam practice
WORKED EXAMPLE
Compare the multi-store model and the working memory model. [ERQ paragraph]
Similarity
Both are cognitive models specifying capacity and duration, and both are supported by lab experiments and case studies.
Key differenceThe MSM is linear; the WMM is parallel. Only the WMM can explain doing two tasks at once.
Evidence
Baddeley’s dual-task findings need separate slave systems; a single STM store cannot account for them.
Judgement
They answer different questions: the MSM maps the whole system, the WMM explains one part of it in depth.
Compare, do not just describeUse “whereas” at least twice. It forces genuine comparison.
WORKED EXAMPLE
Contrast the two models with reference to one limitation each. [3 marks]
1. MSM limitation
It treats LTM as one store, when episodic, procedural and semantic memory clearly differ.
2. WMM limitationThe central executive is almost impossible to test, so it remains hypothetical.
3. The contrast itself
The MSM is too simple about what it covers; the WMM is too vague about what it leaves out.
Two limitations plus the contrastThe third sentence is what makes it a contrast rather than a list.
💡 Exam tip
Open with scope: the MSM covers three stores, the WMM covers one. It frames everything else.
“Compare” means similarities and differences. “Contrast” means differences only. Read the command term.
Use one shared study — HM supports both models, which makes a neat similarity point.
Parallel processing is the single strongest advantage of the WMM. Say it explicitly.
Cultural relativism applies to both. That is a rare evaluation point students miss.
Never conclude “the WMM is better” without saying at what.
⚠️ Common mix-up
The WMM did not replace the MSM. It replaced the STM box within it.
Do not say the MSM ignores rehearsal. Rehearsal is central to it; the WMM is the vague one about LTM.
Two paragraphs of description is not a comparison. Alternate within paragraphs.
Both have lab support. Students often claim only one is experimentally backed.
Unitary means “a single undivided store”. It does not mean “united”.
Case studies support both models — and limit both, for the same reason.
Up next: How Culture Shapes What We Remember — both models assume memory works the same way in everybody. The next three pages test that assumption.
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