WMM and features

• WMM EVALUATION

  • Came about as MSM inadequate and too simplistic
  • Shows STM has multiple stores
  • Arrows going both ways as shows constant flow of info
  • Extension of MSM which is linear
• Problems with WMM


  • Don't know exactly how it works
  • Don't know what episodic buffer is
  • Research lab experiment lacks ecological validity - artificial
• Assume that's how it happens
• CENTRAL EXECUTIVE


  • Supervisory Role
  • Monitors incoming data
  • Focuses attention
  • Allocates subsystems to tasks
  • Limited storage capacity so cant attend to many things at onces
  • Does NOT store info
  • Drives systems
  • Most important as in control of PL and VSS
• Visual Spatial Sketchpad

  • Stores visual + spatial info for very short time
  • Limited capacity (up to 3/4 objects)
  • Subdivided into: Visual cache (stores visual data), Inner scribe (records arrangement of objects in visual field)
  • 2nd subsystem
• Phonological loop

  1st subsystem

  Auditory info - acoustic coded

  Preserves order of info

  Subdivided into:

  Phonological store - stores words u hear for 1-2 seconds

  Articulatory process - allows maintenance rehearsal, rehearses speech i phonological store

  Memory traces in phonological store last 1.5-2 sec, can be maintained by articulatory process
• After brain injury, STM for auditory info is poor


  But visual info is unaffected

  e.g When made to recall letters and digits recall is better when someone else reads them out compared to when we read them ourselves

  shows phonological loop damaged but visual spatial sketchpad intact

  This supports the existence of separate visual and acoustic memory stores
• Investigating the central executive


  1. Participants asked to think of random digits

  2. Carried out on its own or 3 other conditions:

  - Carried out with reciting the alphabet

  - Carried out with counting from 1

  -Carried out with alternating between letters and numbers

  Generated number stream much less random,, baddeley sed central xecutive fightin fo same limited resources
• Episodic buffer


  • General storage space for both acoustic and visual information
  • Integrates information from the central executive, the phonological loop, the visual sketchpad and the long-term memory
  • Has limited capacity
  • Stage component for central executive
  • Links WM to LTM
• Investigating the phonological loop


  1. Presented words for very brief periods of time

  2. One condition: 5 words, one syllable, familiar

  3. Two condition: 5 polysyllabic words
• Word length effect


  Participants remembered the short words much better, shows the limited capacity of the articulatory process (about 2 seconds) so longer words take longer to rehearse
• Articulatory suppression


  Word length effect disappeared (short words recalled no better than long words) under conditions of articulatory suppression (saying la-la-la-la-la), shows word length effect depends on having a verbal rehearsal system
• Investigating the visuo-spatial sketchpad

  1. Participants given a visual tracking task: following a spot of light with a pointer as it moved round a circular path

  2. Carried out with describing the angles of the letter F

  3. Carried out with performing a verbal task
• This supports the existence of a separate slave system (the visuo-spatial sketchpad) that deals with visual information, and shows that the VSS has a limited capacity
• Visuo-spatial sketchpad


  • Deals with visual information
  • Has limited capacity
• Visual tracking task


  1. Following a spot of light with a pointer as it moved round a circular path

  2. Describing the angles of the letter F

  3. Performing a verbal task
• Condition 1


  Involves the visuo-spatial sketchpad for both tasks
• Condition 2


  Involves both the visuo-spatial sketchpad (to trace the line) and the phonological loop (to perform the verbal task)
• Participants found it very difficult to track the spot of light and accurately classify the corners but found it easier to do the tracking task at the same time as performing a verbal task
• This supports the existence of a separate slave system (the visuo-spatial sketchpad) that deals with visual information
• Visuo-spatial sketchpad

  • Has a limited capacity
• Patient KF had difficulties recalling auditory information from STM but not visual information
• This suggests that his damage mainly affected the phonological loop as he appeared to be able to use the visuo-spatial sketch pad
• This also supports the proposed idea of multiple components to STM, as proposed by the working memory model
• Most studies of brain damage are case studies; whilst case studies provide a lot of detail, the participants may have unique characteristics which mean that they are not representative of the wider population
• It is also not possible to make before and after comparisons of their memory deficits as we do not know how they were before they sustained the brain damage
• The trauma of the brain injury may have resulted in numerous changes in behaviour
• These limitations undermine the extent to which we can rely on studies of patients with brain damage to evaluate the working memory model
• fMRI scans: Braver et al. (1997) found that when their participants were performing activities involving the central executive while being scanned the prefrontal cortex showed greater activity
• The activity was increased if the activity was harder
• This supports the existence of the central executive
• The central executive is the most important but the least understood component of the working memory according to Baddeley, 2003
• Some psychologists suggest that it might consists of separate components
• Both models have empirical support (studies supporting them)
• The empirical support for both models is based mainly on lab experiment so there is a lack of ecological validity as it does not reflect the way we use our memory in everyday life i.e. We do not usually learn list of words without meaning