Working Memory Model

Working Memory Model

1. Baddeley and Hitch (1974)

   • Wasn't just one store but a number of different stores
   • If you do 2 things at the same time and they are both visual tasks, you perform them less well
   • If you do 2 things at the same time and one is visual and the other involves sound, then there is no interference meaning you do them as well simultaneously as you would separately

2. Central executive

   • Function is to direct attention to particular tasks
     • Determining at any time how the brains resources are allocated to tasks
       • The resources are the three slave systems
   • Data arrive from the senses or from long-term memory
   • Very limited capacity, cannot attend too many things at once
   • Has no capacity for storing data

3. Phonological loop

   • Limited capacity
   • Deals with the auditory information and preserves the order of the information
   • Baddeley (1986)
     • Further subdivided this loop into
       • Holds the words you hear, like an inner ear
       • An articulated process which is used for words that are heard or seen, silently repeated like an inner voice
         • Form of maintenance rehearsal

4. Visuo-spatial sketchpad

   • Used when you have to plan a spatial task (like getting from one room to another)
   • Visual information is temporarily stored here
   • Spatial information is the physical relationship between things
   • Logie (1995)
     • Can be divided into
       • A visual cache which stores information about visual items (form or colour)
       • An inner scribe which stores the arrangement of objects in the visual field

5. Episodic buffer

   • Baddeley (2000)
     • Added this store because he realised the model needed a general store
   • Extra storage system that has limited capacity
   • Integrates information from the central executive, the phonological loop and the visuo-spatial sketchpad
   • Maintains a sense of time sequencing, basically recording events that are happening
   • Sends information to the LTM

6. Strengths

   • Dual task performance
     • Supported the existence of the central executive in one study
     • Task 1 occupied the central executive (eg participants were given a statement 'B is followed by A' and shown two letter such as AB and asked to say true or false)
     • Task 2 either involved the articulatory loop (eg asked to say 'the, the, the' repeatedly or involved both the central executive and the articulatory loop (saying random digits)
     • Task 1 was slower when Task 2 involved both the central executive and the articulatory loop
     • This demonstrates the dual task performance effect and shows that the central executive is one of the components of working memory
   • Evidence from brain-damaged patients
     • Shallice and Warrington (1970)
       • Studied a man can KF whose short-term forgetting of auditory information was much greater than that of visual stimuli
         • His auditory problems were limited to verbal material such as letters and digits but not meaningful sounds, his brain damage seemed to be restricted to the phonological loop
       • Another patient SC had generally good learning abilities with the exception of being unable to learn word pairs that were presented out loud
         • This suggests damage to the phonological loop (Trojano and Grossi 1995)
       • Another patient LH who had been involved in a road accident performed better on the spatial tasks than those involving visual imagery (Farah et al 1988) this suggests separate visual and spatial systems

7. Limitations

   • The central executive
     • Doesn't state exactly what it is
     • Too vague
     • Notion of a single central executive is wrong and that there are probably everal components
     • Eslinger and Damasio (1988)
       • Studied EVR who had had a cerebral tumour removed
         • He performed well on tests requiring reasoning which suggested that his central executive was intact however he had poor decision making skills suggesting that in fact his central executive was not wholly intact
       • Probably more complex than portrayed
   • Use of case studies with brain-damaged patients entails a number of problems as the process is traumatic and it in itself will change behaviour which might mean that the persons performance is worse on certain tasks
   • Individual differnces