AO3

• A strength is that it is supported by clinical evidence.

  -Shallice and Warrington (1970) studied KF, a patient with brain damage who had poor verbal STM but normal visual STM.

  -This suggests the phonological loop and visuospatial sketchpad are separate, supporting the idea of different stores.
• A criticism of the WMM is that the idea of a central executive is too vague

  -The central executive is said to control attention and coordinate tasks, but there's little evidence showing how it does this or whether it is truly a single system.

  -This vagueness limits the explanatory power of the model and suggests it may need further development.
• A strength is that Supporting evidence for the PL comes from the word length effect

  -Baddeley et al (1975) found that people have greater difficulty remembering a list of long word compared to a list of short words – the word length effect. This is because of the limited space for rehearsal (about 2 seconds) in the articulatory process.
• This effect disappears if

  he participant is given an articulatory suppression task (e.g. repeating “the”). It means you are unable to repeat the shorter words more quickly than the longer ones. This demonstrates the existence of the PL and the articulatory process.
• A strength is V.K Simms et al

  -got ppts to solve mental animations while simultaneously imagining dots on a grid or doing verbal tasks.

  -ppts could do one verbal + visual but not 2 visual

  -this shows WMM has limited capacity and more than one component/slave systems
• Another limitation is that evidence often comes from case studies of brain-damaged patients.

  -While informative, these are unique cases and may not be generalisable to everyone.

  -This means the findings may lack population validity.