Working Memory Model

• WMM

  Involves temporarily storing, manipulating and actively processing information in STM. Baddeley and Hitch created this theory and they said its an improvement of MSM as it recognises that STM is not a single unitary store. Instead they are made up of multiple distinct components.
• Key study - Baddeley and Hitch (Dual task study)


  PP were asked to perform two tasks at the same time. A digit span task required them to repeat a list of numbers and a verbal reasoning task (answer true or false questions). Conclusion - the verbal reasoning task made use of central executive and digit span made use of phonological loop. the random digit task interfered with verbal reasoning performance therefore supports idea of sperate stores in WM.
• The central executive 


  most important as responsible for monitoring and coordinating the operation of the slave systems. Role is paying attention, planning and synthesising information in slave systems and in LTM.
• Evaluation of Central Executive

  Research support- Baddeley found PP had difficulty generating lists of random numbers while switching between pressing numbers and letters on a keyboard. Suggests two tasks were competing for resources suggests it has limited capacity. CE is vague - criticised for being too simple and untestable as its unclear how it operates.
• The visuo-spatial sketch-pad


  This stores visual and spatial items and shows the relationship between them. Can be though of as the inner eye.
• Evaluation of VSS

  Dual task technique - it effectively accounts for our ability to store information briefly while processing information. The model has proven influential and is still being developed and explained.
• The phonological loop

  processes auditory information and maintains the order of additonary info. This stores a limited number of sounds for brief periods and can be though as the inner ear.
• Evaluation of PL


  Baddeley reported on the word length effect where pp recalled more short words in order than longer words, supports the capacity of PL is set by how long it takes to say words rather than actual numbers of words.
• The episodic buffer


  Baddeley added this as a third slave system as the model was missing a general store to operate. The PL and the VSS deal with the processing and temporary storage of specific types of information. Limited capacity and no storage so can't contain items relating to visual or acoustic info.
• Evaluation - WMM 


  case study- KF was in a motorcyclist accident, damaged his STM specifically verbal recall but still has good VSS memory. suggests WMM has different components as separate components PL for verbal and VSS for visual.
• Evaluation of WMM.

  Dual Task studies - used to see if certain mental functions work separately or share same resources. Baddeley and Hitch found PP made more errors when one task was auditory and onw task was visual but more errors made when tasks were both auditory and visual . Shows when both resources are used they are compering for the same resources so causes impaired performance.