Working Memory Model

BADDELEY AND HITCH (1974)

The working memory model was introduced by Baddeley and Hitch. It takes place in the short term memory.

Central Executive

      Phonological Loop                     Episodic Buffer                  Visuo-Spatial Sketchpad

   Articulatory       Phonological                                                        Visual              Inner

      Loop                     Store                                                                  Cache             Scribe

The central executive monitors incoming data and allocates slave systems to tasks. It is for this reason it is the most important part of the short term memory.

It has a limited storage capacity.

The phonological loop processes auditory information and preserves the order in which the information arrives. It consists of two subdivisions. The phonological store and the articulatory process.

The phonological store stores words that are heard.

The articulatory process allows maintenance rehearsal - rehearsal of sounds to keep them in the short term memory.

The visuo-spatial sketchpad stores visual and spatial information. It is divided into two subdivisions, the visual cache and the inner scribe.

The visual cache stores visual data.

The inner scribe records arrangement of objects in the visual field.

The episodic buffer was added to the model in 2000 as a way of explaining the actions that require both verbal and visual/spatial information at the same time. An example would be tuning and instrument.

It is a tempoary store for information. It processes information that is also processed by the other slave systems.

The episodic buffer maintains a sense of time sequencing and links to the long term memory.

KF case study supports it - Shallice and Warringon (1970) carried out a case study of patient KF who had brain dmamge. He had poor short term memory ability for verbal information but could process visual information. This means his phonological loop was damaged but other areas were still intact - High reliability

Dual tasks support the visuo-spatial sketchpad - Baddeley (1975) found that participants had more difficulty doing two visual tasks than doing a verbal and visual task at the same time. This is because both visual tasks are competing for the same limited resources; when doing a verbal and visual task there is no competition

The word length effect supports the phonological loop - Baddeley (1975) found that people have more difficulty remembering a list of long words than short words. This is because there is limited space for rehearsal in the articulatory process. The word effect dissappears if someone is given a repetitive task tying up the articulatory process and demonstrating the process at work

Brain scan studies support the model - Braver (1997) had particioants do tasks involving the central executive while they were having a brain scan. Activity was seen in the prefrontal cortex; activity increased as the task became more difficult. This means that as the demands of the central executive increase it has to work harder to fulfil its function - High reliability

There is a lack of clarity over the central executive - Some psychologists believe that the central executive is unsatisfactory and does not really explain anything. It should be more specified than just being 'attention'. Some psychologists think it is made up of different components. This means that the working memory model isn't fully explained