MEMORY: the working memory model

Description of the WMM AO1

• alternative model to the MSM - it addresses one aspect of memory - short term memory

• baddeley and hitch thought the STM was not just one store because:

  • if you do two things at the same time (dual task performance) and they are both visual tasks, you perform them less well than if you do them separately

  • if you do two things at the same time and one is visual nd another involves sound, then there is no interference. You do them as well simultaneously as you would do them separately

• this suggests that there is one store for visual processing and a separate store for processing sounds. This formed the basis of the WMM where ‘slave systems’ were organised by a central executive

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 3 slave systems (phonological loop, visa-spatial sketchpad, episodic buffer)

CE has a very limited capacity - and has no capacity for storing data

phonological loop

• has a limited capacity

• deals with AUDITORY INFORMATION and preserves the order of information. Baddeley further subdivided this group into

  • phonological store which holds the words you hear like the inner ear

  • an articulatory process which is used for words that are heard or seen. these words are silently repeated, like an inner voice - this is a form of maintenance rehearsal

• if your mother tries to speak to you while watching he TV, you find it difficult to listen to them at the same time - because of the limited capacity of the phonological loop

Visuo-spatial sketchpad

• used when you have to plan a spatial task (e.g getting from one room to another, counting the windows in your house)

• visual and/or spatial information is temporarily stored here.

• visual information is what things look like

• spatial information is the physical relationship between things

• Logie 1995 suggested that the visa-spatial sketchpad can be divided into

  • a visual cache which stores information about the visual items e.g form and colour

  • an inner scribe which stores the arrangement of objects in the visual field

  • E.g Wayne Gretzky scored a goal one occasion by hitting a puck so it bounced off the goalies back and into the goal - he was able to visualise the spatial relationship between objects, even when the objects were in motion.

Episodic buffer

Baddeley added because he realised we needed a general store.

PL and VSS deal with processing and temporary storage of specific kinds of information

CE has no storage capacity so no where to hold info

so there was no where to hold both info that relates both visual and acoustic info

its an extra storage system that has limited capacity

it integrates information from the CE, PL and VSS. It also maintains a sense of time sequencing - recording events (episodes) that are happening which then sends info to LTM

• explains why some patients with amnesia can remember passages from a book when tested fairly immediately despite having no long term recall.

AO3 on the WMM - Brain damage

Studies of individuals with brain damage also support the WMM

Shallice and Warrington 1970 studied a man called KF whose short term forgetting of auditory information was much greater than that of visual stimuli. In addition his auditory problems were limited to verbal material such as letters and numbers but not meaningful sounds (such as phone ringing). Thus 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, suggesting damage to the phonological loop.

this supports the idea of separate visual and spatial systems, as suggested by the WMM

AO3 - Problems of case studies

there are a number of problems with using evidence form the case studies of individuals who have suffered serious brain damage.

Brain injury is traumatic which may in itself change behaviour so that a person performs worse on certain tasks. second such individuals may have other difficulties (individual differences) such as saying attention and therefore underperform on certain tasks. Case studies of individuals are examples of idographic approach to research and this means the unique cases cannot be generalised to the population as everyone is different.

this is an issue for the WMM and as some of the key research that supports the WMM comes from case studies

AO3 - central executive

However, some psychologists feel the concept of the central executive is too vague and doesn’t really explain anything

all it appears to do is allocate resources and essentially eb the same as ‘attention’. Critics also feel that the notion of a single CE is wrong and that there are probably several components.

Eslinger and Damasio 1985 studied EVR, who 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 (he would spend hours trying to decide where toe at for example), which suggests that in fact his CE was not wholly intact.

in summary the account offered of the CE is unsatisfactory beacause it is probably more complex than baddeley and hitch originally suggested.

AO3 - Evidence for the phonological loop and articulatory process

A strength of the WMM lies in the phonological loop and its explanation of the word-length effect - the fact that people can cope better with short words than long words in the working memory (STM)

it seems that the phonological loop holds the amount of information that you can say in 2 seconds (Baddelely). this makes it hard to remember a list of long words such as ‘association and representative’ compared to shorter words like ‘harm and twice’. The longer words can’t be rehearsed on the phonological loop because they don’t fit.

However, the word-length effect disappears if a person is given an articulatory suppression task , for example if you are asked to say ‘the the the’ while reading the words. This repetitive task ties up the articulatory process and means you can’t rehearse the shorter words more quickly than the longer ones, so the word length effect disappears

this is evidence for the articulatory process - a key component of the WMM