The working memory model

• The working memory model (WMM) is detailed model of our short term memory. It was proposed by Baddeley and Hitch.
• The WMM is concerned with the part of our mind that is active when working on an arithmetic problem or comprehending language, etc.
• The Central Executive (CE) allocates slave systems. It is an attentional process that monitors incoming data and allocates slave systems to tasks. It has a very limited storage capacity.
• The Phonological Loop (PL) deals with auditory information and preserves the order in which information arrives. It's subdivided in to the phonological store and the articulatory process.
• The phonological store stores the words you hear
• The articulatory process allows maintenance rehearsal - repeating sounds to keep them in your WM while they're needed.
• Our visuo-spatial sketchpad (VSS) stores visual and/or spatial information when required. Logie (1995) subdivided the VSS in to the visual cache (stores visual data) and the inner scribe (records the arrangement of objects in the visual field).
• The episodic buffer is temporary storage that was added in 2000. It intergrates visual, spatial, and verbal information from other stores. It also links to our LTM and maintains our sense of time sequencing.
• A limitation of the WMM is that there is a lack of clarity over the central executive. Cognitive psychologists argue that the CE is unsatisfactory and doesn't really explain anything. The CE should be more specific that being simply 'attention' - some psychologists believe it may consist of separate elements. This means that the WMM hasn't been fully explained.
• A strength of the WMM is that the word length effects supports the work of the phonological loop. Baddeley (1975) found that people have more difficulty remembering a list of long words than short words. This is because there's limited space for rehearsal in the articulatory process. The word length effects disappears if a person is given a repetitive task tying up the articulatory process, demonstrating the process at work.
• A further strength of the WMM is the support from brain scanning studies. Braver's (1997) participants performed tasks involving the CE while being scanned. Activity was seen in the area known as the prefrontal cortex. Activity increased at the task became harder. This makes sense: as demands of the CE increase, it has to work harder. This study provides evidence that the CE may have a physical reality in the brain.