Working Memory Model

• Central Executive


  Capacity = Limited Storage

  Coding = Any type of information - modality specific

  Duration = N/A

  The central executive is an attentional process that monitors incoming data and decides what needs to be done and delegates tasks

  Keeps an eye on what is happening in the slave systems and takes over the most demanding task where necessary

  Any task that requires attention will overload the CE as it has a very limited capacity
• Phonological Loop (Slave One)


  Capacity = Limited (seconds)

  Coding = Acoustically

  Duration = 2 seconds

  Auditory information is passed from the CE to the phonological loop.

  Baddeley further subdivided the PL into 2 parts;

  The phonological store- which stores the words we hear

  The articulacy process - silently repeats words that are seen or heard, like an inner voice (maintenance rehearsal occurs here)
• The Visuo-Spatial Sketchpad (Slave Two)


  Capacity = Limited (3/4 objects)

  Coding = Visually

  Duration = N/A

  Visual Cache - stores visual data

  Inner scribe - records the arrangement of objects in the visual field

  It is responsible for setting up mental images and is what you use if you have to plan a spatial task e.g giving directions

  It temporarily stores visual and spatial info
• The Episodic Buffer (Slave Three)


  Capacity = Limited (about 4 chunks)

  Coding = Any type of information

  Duration = N/A

  This is a general store, later added by Baddeley and Hitch in 2000 The EB collects and combines information from the CE, PL and VSS to record an event. The EB transfers information to the LTM and is used to retrieve information from the LTM to the STM
• AO3 WMM: Dual Task Performance

  • Another strength is that dual-task performance support the separate existence of the visuo-spatial sketchpad
  • Baddeley made PPs do 2 visual tasks and then 1 verbal and 1 visual task
  • Both visual tasks compete for the same subsystem (VSS) whereas there is no competition when performing a verbal and visual task together suggesting there is a separate subsystem (VSS) that processes visual input and one for verbal processing (PL)
  • Supports the idea there are separate components within STM due to limited capacity
• AO3 WMM: Lack of Clarity over the Central Executive

  • Despite the empirical research to support the WMM, some argue that much of this research is conducted on the slave systems such as the PL and VSS and that there is a lack of clarity over the role of the CE
  • The CE is said to be a single component of 'attention' that delegates to slave systems, however some psychologists suggest that the central executive may have several components within it
  • This casts doubt on the WMM as an explanation of STM
• AO3 WMM: Clinical Evidence

  • Research to support the WMM was conducted by Shallice and Warrington on patient KF who suffered with amnesia
  • They found that KF's recall in STM for digits was very poor when the digits were read aloud to him
  • Recall was much better when KF could read the digit himself
  • This supports the WMM because it suggests that there must be different stores within the STM one to process visual information (VSS) and one to process auditory information (PL)
  • In KF's case his PL was damaged but the VSS intact
• AO3 WMM: Counterpoint to KF

  • However, critics would argue that the case study to support the WMM is flawed as it has low population validity
  • The research was a case study of just one person KF who has an unusual illness involving damage to the brain
  • It is difficult to generalise the findings to the wider population as their STM may operate differently thus limiting the support that the research provides for the working memory model
• AO3 WMM: Counterpoint to KF

  • It is unclear whether KF had other cognitive impairments (apart from damage to his phonological loop)
  • This might have affected his performance on memory tasks
  • His injury was caused by a motorcycle accident and the trauma involved may have affected his cognitive performance quite apart from any brain injury
  • This challenges evidence that comes from clinical studies of people with brain injuries that may have affected many different systems
• AO3 WMM: Validity of the Model

  • Dual-task studies support the WMM because two tasks that share a subsystem are much harder to perform together than tasks that involve separate subsystems
  • Therefore, there must be separate components in working memory (VSS and PL)
  • These studies use tasks that are very unlike the tasks we perform in our everyday lives (identifying the correct order of letters)
  • They are also carried out in highly-controlled lab conditions