WMM - Baddeley & Hitch

• Baddeley and Hitch (1974)


  Developed the Working Memory Model (WMM), which focuses specifically on the workings of short-term memory (STM)(multi-component short-term memory).
• Atkinson and Shiffrin's Multi-Store Model of memory (MSM)

  Criticised for over-simplifying STM (as well as LTM) as a single storage system
• Working Memory Model (WMM)

  1. Proposes that STM is composed of three, limited capacity stores:

  2. Central Executive - manages attention, controls information from the two 'slave stores'

  3. Articulatory-Phonological Loop - temporarily retains language-based information, consisting of an articulatory rehearsal process ('inner voice') and a Phonological store ('inner ear')

  4. Visuo-Spatial Sketchpad - temporarily retains visual and spatial information
• Episodic buffer


  Later added - Facilitates communication between the central executive and long term memory
• Dual-task technique (or 'interference tasks')


  Performance is measured as participants perform two tasks simultaneously
• If one store is utilised for both tasks

  Task performance is poorer than when they are completed separately, due to the store's limited capacity. e.g. repeating “the the the” aloud and reading some text silently would use the articulatory-phonological loop for both tasks, slowing performance.
• If the tasks require different stores

  Performance would be unaffected when performing them simultaneously
• Working Memory Model


  • Provides an explanation for parallel processing, unlike Atkinson and Shiffrin's MSM
  • Supported by a case study of brain-damaged patient KF who could recall verbal but not visual information immediately after presentation
• The WMM was developed based on evidence from laboratory experiments, so confounding variables could be carefully controlled to produce reliable results (that can be replicated)
• The WMM has been criticized for being too simplistic and vague, e.g. it is unclear what the central executive is, or its exact role in attention
• Results from laboratory experiments researching the WMM will often have low ecological validity (i.e. may not relate to real life), as tasks such as repeating 'the the the' are arguably not representative of our everyday activities
• What's the central executive?

  Known as the 'boss' of WMM, manages attention.
• What does the Phonological loop consist of?

  Articlatory control process & Phonological store
• Articulatory rehearsal process ('inner voice')

  Language, including any language presented visually, is converted to a phonological state
• Phonological store ('inner ear')

  Holds auditory speech information and the order in which it was heard (or any visually-presented language converted by the articulatory process)
• Visuo-Spatial Sketchpad

  Temporarily retains visual and spatial information
• Weaknesses of the Working Memory Model (WMM)

  • Provides more detail of Short-Term Memory (STM) than the multi-store model
  • Criticized for being too simplistic and vague e.g. it is unclear what the central executive is, or its exact role in attention.
• Results from laboratory experiments researching the WMM will often have low ecological validity (i.e. may not relate to real life)
• Tasks such as repeating 'the the the' are arguably not representative of our everyday activities