The working Memory Model

• The working memory model


  The working memory model was proposed as a replacement of the MSM’s idea of a unitary STM i.e. the idea that there is a single STM store. It also proposed that STM does not simply act as a passive, temporary store for transferring information to LTM. In contrast, the WMM suggests a working memory comprises of a system that actively processes and stores information. It thus replaced ‘short-term’ memory with the name of ‘working memory’.
• Central executive 


  Processes information in all sensory

  forms (e.g. acoustic and visual) and directs this

  information to the model’s slave systems. Because it has

  a limited capacity, it also controls the division and

  allocation of our attention to tasks.
• Phonological Loop


  One of the slave systems controlled by the central executive. It deals with auditory information that is coded acoustically. The phonological loop is subdivided into the:

  • Phonological store – stores the words you hear in speech form.

  • Articulatory process – allows for maintenance rehearsal (repeating sounds/words) to keep them in working memory while they are needed. The capacity of this ‘loop’ is limited to what can be said in approximately 2 seconds.
• Visuo-spatial sketchpad (VSS)


  One of the slave systems controlled by the

  central executive. It processes and stores visual

  information (what objects look like) and spatial

  information (where they are in the environment). It

  codes informational visually and is limited to a capacity

  of 3-4 objects. The VSS is subdivided into the:

  • Visual cache: Stores visual information (e.g. about form and colour).

  • Inner scribe: Records the arrangement of objects in the visual field (i.e. where they are)
• Episodic buffer


  the third slave system that was later added

  to the model. It is a general storage space for acoustic, visual and spatial information. It therefore integrates information from the phonological loop and the visuo-spatial sketchpad to form whole ‘episodes’ of information. It has a limited capacity of about 4 chunks of information.
• What is a strength of the Working Memory Model (WMM)?

  There is supporting evidence for the existence of different slave systems and their limited capacity.
• What did Shallice and Warrington's case study of patient KF demonstrate?

  KF's STM for digits was poor when read aloud but better when he read them to himself.
• What does KF's case study suggest about working memory stores?

  It suggests there are different working memory stores for visual and auditory information.
• What do dual task studies indicate about task completion?

  It is easier to complete two tasks simultaneously if they use different processing systems.
• What are the two proposed slave systems in the WMM?

  The phonological loop and the visuospatial sketchpad.
• What does Baddeley's (1975) experiment demonstrate about the phonological loop?

  It is limited to what can be said in approximately 2 seconds.
• What were the two conditions in Baddeley's experiment?

  Participants were presented with monosyllabic and polysyllabic words.
• What was the outcome of Baddeley's experiment regarding word recall?

  Participants remembered more monosyllabic words than polysyllabic words.
• What does the word length effect indicate about the phonological loop?

  The capacity is determined by how long it takes to say words, not the number of words.
• What supporting evidence exists for the central executive in the WMM?

  D'Esposito et al. (1995) found activation in the prefrontal cortex during simultaneous verbal and spatial tasks.
• What happens to the prefrontal cortex during difficult tasks?

  Greater activity is observed as tasks become more difficult.
• Why is the central executive considered vague and untestable?

  Little is known about how it allocates attention to different slave systems.
• What limitation does Baddeley recognize about the central executive?

  It is the least understood component of the WMM.
• How did the WMM advance the Multi-Store Model (MSM)?

  It explained that STM is not a unitary store and comprises multiple components.
• How does the WMM depict STM compared to the MSM?

  It depicts STM as an active process rather than a passive 'stopping-off station'.
• What practical application has arisen from the WMM's findings?

  Texting while driving is banned due to the risk of overloading the visuospatial sketchpad.
• What does the increased likelihood of car accidents relate to in the context of the WMM?

  It relates to the difficulties experienced when overloading the same visuo-spatial slave system.
• What are the key components of the Working Memory Model (WMM)?

  • Central Executive
  • Phonological Loop
  • Visuospatial Sketchpad
  • Episodic Buffer
• What are the strengths and limitations of the Working Memory Model (WMM)?

  Strengths:

  • Evidence for different slave systems
  • Evidence for limited capacity of phonological loop
  • Support for the central executive

  
  

  Limitations:

  • Central executive is vague and untestable
  • Not fully explained