Working Memory Model - Baddeley & Hitch (1974)

Working Memory Model - Baddeley & Hitch (1974)

1. Thought MSM explanation of STM too simplistic

   • WMM focused on STM and believed it was not a unitary store
   • WMM consists of a central executive and 3 slave systems

2. Central Executive

   • Allocates information to the slave systems
   • Deals with cognitive tasks e.g. decision making and problem-solving
   • Gives priority to certain tasks
     • Allows working memory to respond to certain stimuli but ignore others

3. Phonological Loop

   • Coded acoustically
   • Capacity = 2s worth of words
   • Subdivided into phonological store and articulatory process
     • Phonological store
       • Holds auditory speech information in speech-based form
       • Spoken words enter directly; written words first converted to articulatory code
     • Articulatory process
       • Acts like an inner voice rehearsing information from phonological store
         • Acts like maintenance rehearsal
       • Coverts written material into articulatory code and transfers it to phonological store

4. Visuo-Spatial Sketchpad

   • Stores visual and spatial information
     • Visual = what things look like Spatial = relationship between things
   • Helps us keep track of where we are in relation to other objects as we move through our environment
   • Displays and manipulates visual and spatial information held in LTM
   • Logie (1995) suggested subdivision:
     • Visuo-cache (stores visual data)
     • Inner scribe (arranges spatial relations in our visual field)
   • Capacity = 3-4 objects

5. Episodic Buffer

   • Baddeley (2000) added episodic buffer as model needed a more general store
   • Used a backup when CE is overloaded
   • Integrates information from other areas e.g. LTM
   • Capacity = 4 chunks

6. Evidence (strengths of WWM)

   • Baddeley & Hitch (1976)
     • Pps performed 2 tasks simultaneously
       • Task 1: True or false quiz - used CE as tested verbal reasoning
       • Task 2: Either - say 'the the the' (uses articulatory loop) OR say random digits (uses CE and AL)
       • Results: quiz was slower when given the second task that used CE and AL
         • Conclusion: Completing 2 tasks involving same component is difficult. Show the different components of STM and supports CE
   • Evidence for VSSP: Baddeley (1975)
     • Pps performed 2 tasks simultaneously
       • Task 1: Visual tracing task (tracking moving light with pointer)
       • Task 2: Either - describe angles on letter F, OR do a verbal task
       • Found difficult to describe F as both task 1 and 2 used VSSP
   • Evidence for EB: Baddeley et al. (1987)
     • Pps shows words, then immediately recall
       • Recall better for sentences (related words) than unrelated words
         • Supports idea of a general memory store that draws on LTM (EB)
   • Real-life cases: KF
     • Brain damage from motorcycle accident
     • Memory of auditory information damaged but memory for visual information unaffected
       • Shows different stores (VSSP + PL)

7. Limitations

   • Lieberman (1980) criticises WMM for saying that visual and spatial info are linked
     • Blind people have good spatial awareness without visual info
     • Suggests VSSP split into 2 components
   • Little evidence for how CE works or what it does + capacity never measured
   • Not a comprehensive model of memory as only includes STM
   • Does not explain changes in memory processing due to practice or time