working memory model

• ao1: what is the WMM? + Diagram

  • The Working Memory Model (WMM), proposed by Baddeley and Hitch (1974), explains how information is temporarily stored and manipulated for cognitive tasks. It consists of several components:

  
• ao1: wmm component

  1. Central Executive is the control system that coordinates information from the other stores. It has limited capacity and allocates resources to the phonological loop, visuospatial sketchpad, and episodic buffer.
  2. The Phonological Loop processes auditory information and consists of two subcomponents: the phonological store (inner ear), which holds verbal information briefly, and the articulatory rehearsal system (inner voice), which repeats information to keep it in the loop.
  3. The Visuospatial Sketchpad handles visual and spatial information, such as remembering shapes and navigating through space.
  4. The Episodic Buffer, added by Baddeley in 2000, integrates information from the central executive, phonological loop, and visuospatial sketchpad into a unified episode and links working memory with long-term memory.
• ao1: WMM coding and capacity for each store

  • CE: coding is flexible; capacity is very limited. (NB Recent views suggest there may be no storage capacity at all.)
  • PL: coding is acoustic, capacity is about two seconds' worth of what you can say.
  • VSS: coding is visual and spatial, capacity is three or four objects.
  • EB: coding is flexible, capacity is about four 'chunks'.
• ao3: One strength of the model is support from clinical evidence.

  • For example, Shallice and Warrington (1970) studied patient KF who had a brain injury.
  • His STM for auditory information was poor (damaged PL) but he could process visual information normally (intact VSS).
  • This supports the WMM view that there are separate visual and acoustic memory stores.
• ao3: COUNTERPOINT TO KF STRENGHT

  • KF may have had other impairments which explained poor memory performance, apart from darnage to his PL.
  • This challenges evidence from clinical studies of brain injury.
• ao3: Another strength is that dual task performance studies support the VSS.

  • Baddeley et al.'s (1975) participants found it harder to carry out two visual tasks at the same time than do a verbal and a visual task together. (Same for two verbal tasks.)
  • This is because both visual tasks compete for the same subsystem (VSS). There is no competition with a verbal and visual task.
  • Therefore there must be a separate subsystem that processes visual input (VSS) and also a separate system for verbal processes (PL).
• ao3: One limitation is a lack of clarity over the central executive.

  • Baddley (2003) said the CE was the most important but the least understood component of working memory.
  • There must be more to the CE than just being 'attention' e.g. it is made up of separate subcomponents
  • Therefore the CE is an unsatisfactory component and this challenges the integrity of the model
• ao3: validity of the model

  • Dual-task studies support the WMM because they show that there must be separate components processing visual (VSS) and verbal information (PL).
  • However, these studies are highly-controlled and use tasks that are unlike everyday working memory tasks (e.g. recalling random sequences of letters).
  • This challenges the validity of the model because it is not certain that working memory operates this way in everyday situations