The Working Memory Model (WMM) Flashcards
(17 cards)
What is the WMM a model of?
A model of the STM only.
What did Baddeley and Hitch (1974) argue about the STM?
Baddeley and Hitch (1974) argued that STM is much more complex than a ‘stopping off’ point for information on its way to LTM. They argued that STM is:
• an ACTIVE store that can hold and manipulate information
• as made up of SEVERAL STORES (slave systems)
• can perform DIFFERENT TASKS at the SAME TIME
• has a LIMITED CAPACITY and DURATION
This is called the working memory model (WMM) and the WMM is concerned with the active mind when we are temporarily storing and manipulating information. For example, when working on an arithmetic problem or playing chess or comprehending language etc. It consists of four main components, each of which is qualitatively different, especially in terms of capacity and coding.
What are the similarities between the WMM and MSM?
They both have a limited capacity and duration.
What are the differences between the WMM and MSM?
-WMM has several stores, MSM only has one
-WMM can perform different tasks at the same time, MSM can perform one task at the same time
-WMM is an active store (can hold and manipulate information), MSM is a passive store (can rehearse information only)
-WMM is a model of STM only, MSM involves the STM, LTM and sensory registers
What are the components of the WMM?
-Central executive
-Visuo-spatial sketchpad, which contains the visual cache and the inner scribe
- Phonological loop, which controls the articulatory control system and the phonological store
-Episodic buffer
What are the two slave systems?
The visuo-spatial sketchpad and the phonological loop
What is the central executive?
An attentional process that monitors incoming data, directs attention (decides what to pay attention to), makes decisions and allocates tasks to slave systems. The central executive has a very limited storage capacity.
What is the phonological loop?
Processes auditory information (i.e. coding is acoustic) and preserves the order in which the information arrives. Responsible for processing SOUND based information. It is subdivided into:
a) The phonological store (The inner ear) which stores the words/sounds you hear
b) The articulatory process (The inner voice) which allows maintenance rehearsal (repeating sounds or words in a loop to keep them in working memory while they are needed). The capacity of this loop is believed to be two seconds worth of what you can say in that time
What is the visuo-spatial sketchpad?
Processes visual and spatial information (i.e. coding is visual/spatial). It has a limited capacity which according to Baddeley (2003) is about three or four objects. Logi (1995) subdivided the VSS into:
a) The visual cache which stores visual data
b) The inner scribe which records the arrangements of objects in the visual field (spatial information).
What is the episodic buffer?
This was added to the model by Baddeley (2000). It is a temporary store for information, acting as a storage component for the central executive and has a limited capacity of about four chunks. Integrates visual, spatial and verbal information processed by other stores and maintains a sense of time sequencing – basically recording events (episodes) that are happening. The episodic buffer links working memory to LTM and wider cognitive processes such as perception.
What is dual task performance?
As working memory uses two different slave systems for dealing with visual and verbal information, a visual processing task and a verbal processing task can be performed at the same time with no reduction in performance. However, when we try and perform two visual tasks at the same time, they compete for the visuo-spatial sketchpad and interfere with each other, so performance on both tasks is reduced. The same applies to performing two verbal tasks at the same time.
The working memory model makes the following two predictions:
1. If two tasks make use of the same component of working memory, it is much more difficult to complete each task and performance on each task is reduced.
2. If two tasks make use of different components of working memory, it should be possible to complete each task to an equally high standard as if we were completing them individually.
EVALUATION POINT ONE:
(+) Clinical evidence
Shallice and Warrington (1970) conducted a case study of patient (KF) who had suffered brain damage which resulted in poor STM ability for verbal information (e.g. processing sound). However, KF could still process visual information normally (e.g. processing written letters and digits). This suggests that the brain damage had damaged his phonological loop but not his visuo-spatial sketchpad. This supports the existence of a separate visual and acoustic store and thus gives evidence to support the idea that the phonological loop and visuo-spatial sketchpad are different components of memory.
EVALUATION POINT TWO:
(-) Problems with clinical evidence
Evidence from brain-damaged patients may not be reliable because it concerns unique cases with patients who have had traumatic experiences. This means that these studies may not be generalisable to other people and may not tell us anything about how working memory works in other people.
EVALUATION POINT 3:
(+) Evidence for dual task performance
Baddeley et al. (1975) found that participants had more difficulty doing two visual tasks at the same time compared to doing both a visual and verbal task at the same time as both visual tasks compete for the same slave system (the visuo-spatial sketchpad). This means there must be a separate slave system (the VSS) that processes visual input. This supports the view that the phonological loop and the sketch pad are separate systems within working memory.
EVALUATION POINT 4:
(-) Problems with the central executive
The central executive is the most important but the least understood component of working memory (Baddeley, 2003). We do not really understand how it functions or how it performs tasks such as the allocation of tasks to slave systems. As the central executive is difficult to define, it is difficult to study and there is less evidence to support how it functions. Additionally, some psychologists believe it may not be unitary as the WMM suggests and instead may consist of its own separate components. This means the WMM has not been fully explained so offers only an incomplete explanation of memory.
EVALUATION POINT 5:
(+) Evidence for the phonological loop
Baddeley et al. (1975) found that people find it more difficult to remember a list of long words rather than a list of short words (known as ‘the word length effect’). They found that people could remember the number of words they could say (rehearse) in around 2 seconds which would explain why they could remember more short words (as they can say more short words in 2 seconds than long words). This provides evidence for the existence and capacity of the articulatory process.
EVALUATION POINT 6:
(+) Evidence form brain scanning studies
Braver et al. (1997) gave participants tasks that involved the central executive while they were having a brain scan. The research found greater activity in the left prefrontal cortex. As the task became harder, the activity in this area increased. This not only supports the existence of the central executive, it also has face validity as it makes sense that as demands on the central executive increase (as the task gets harder), it has to work harder to function.
