working memory model

• P: the main reason for developing the WMM was to account for dual task performance, described on the facing page. Hitch and Baddeley supported the existence of the central executive in one study

  E: task 1 occupied the central executive. Task 2 either involved the articulatory loop or involved both the central executive and articulatory loop. Task 1 was slower when task 2 involved both the central executive and articulatory loop

  L: this demonstrates the dual task performance effect and shows that the central executive is one of the components of working memory
• P: studies of individuals with brain damage also support the WMM

  E: shallice and warrington studied a man called KF whose short term forgetting of auditory information was greater than that of visual stimuli. In addition, his auditory problems were limited to verbal material such as letters and digits but not meaningful sounds. his brain damage seemed to be restricted to the phonological loop

  L: this supports the idea of separate visual and spatial systems, as suggested by the WMM
• P: there are a number of problems with using evidence from case studies of individuals who have suffered serious brain damage

  E: the process of brain injury is traumatic, which may in itself change behaviour so that a person performs worse on certain tasks. second, such individuals may have other difficulties such as difficulties paying attention and therefore under perform on certain tasks. case studies are of unique individuals and cannot be generalised to the population

  L: this is an issue for the WMM as some of the key research that supports the WMM comes from case studies
• dual task performance

  • Strength: Participants could complete two tasks simultaneously if they used different components (e.g., visual + verbal), but performance suffered when tasks used the same system (e.g., two verbal tasks).
  • This supports the idea of separate stores (like the phonological loop and visuospatial sketchpad), unlike the unitary STM in the multi-store model.
  • Provides strong experimental evidence for the model’s structure.