The main components of the working memory model are the central executive, the phonological loop, the visuospatial sketchpad, and the episodic buffer. The central executive is atte3ntion to control system which coordinates and monitors the operations of subcomponents: slave systems. The central executive focuses attention and works on dividing attention between tasks as well as shifting attention from one task to another. It controls attention on an automatic level or on the supervisory attention level. The automatic level is based on habits and routine, which require less attention, and the supervisory level deals with developing new strategies through planning and decision making. The phonological loop is the auditory characteristic of short term memory and has two components – the articulatory control system and the phonological store. The articulatory control system can hold information in a verbal form, whereas the phonological store holds memory traces that last from 1.5-2 seconds. Any activity that requires retention of a verbal sequence depends on the phonological loop.
The inner eye of the visuospatial sketchpad, is the visual component of short term memory. It is a temporary store for visual and spatial information. Since all the input is processed in different stores, to understand how we comprehend happenings around us, the episodic buffer was proposed.  This buffer temporarily holds several sources of information active at the same time, while you consider what is needed in the present situation. This means - auditory and visual information together, as well as information from LTM. 

Various studies have been conducted to test the working memory model. One such experiment was conducted by Landry and Bartling in  2011.  Landry and Bartling  conducted an experiment using articulatory suppression to test the Working Memory Model. The aim was to investigate if articulatory suppression would influence recall of a written list of phonologically dissimilar letters in serial recall. The experiment used independent designs with two groups: a control group that performed no concurrent task while memorizing a list and an experimental group, which performed the concurrent task of articulatory suppression while memorizing a list. The participants were randomly assigned to one of the two conditions. The hypothesis was that the accuracy of serial recall would be higher in the control group compared to the experimental group. 

The results of this experiment showed that the experimental group recalled less than the control group, thereby supporting the working memory model. 

How is the link to WMM?

 

They divided the WMM into 4 components:-

1)   The Central Executive: The main/head component of the WMM. Data arrives here from the LTM or the senses and then it acts as a conductor and directs the attention to particular tasks and allocates data to the other systems, also known as the slave systems.

2)   The Phonological Loop: The Phonological Loop is subdivided into two parts - The Phonological Store and the Articulatory Process.

The Phonological Store, or 'inner ear', holds information in speech based form and allows acoustically encoded items to be held for a brief period of time.

The Articulatory Process, or 'inner voice', allows sub-vocal repetition of items stored in the phonological store. This is a form of maintenance rehearsal.

3)   The Visuo-Spatial Sketchpad: Known as the 'inner eye', this component of the WMM is used when you have to mentally plan a spatial task. It stores visual and spatial information.

4)   The Episodic Buffer: It is the general store of the WMM. The Episodic Buffer has a limited capacity and integrates information from all the components of the WMM and also the Long-Term Memory.


STUDY? to support?

This model suggests that there are different stores for visual and auditory processing, rather than a single store as was previously mentioned in the Multi-Store Memory Model. According to them, working memory is a temporary platform that can hold relevant information for use in any cognitive task. That said, as soon as said task is complete, the information disappears to make room for a new round of information processing.

The Working Memory model is a hypothetical model of the Short Term Memory that (as mentioned before) includes multiple different components rather than it being one big store (as it is in the MSM). 

Here, there is a central executive which acts as the attention control system and monitors and coordinates the operations of the other components (which are known as slave systems). In many ways, this is the most important part of the model as it decides how and when the subordinate systems are used. 

While it is able to focus attention, divide it between two or more sources and switch from one task to another, it has limited capacity (meaning it cannot attend to a lot of things at the same time). It is modality-free and can thus process any sensory information, whether it be auditory or visual in nature.

The most important job of this system (attention control) happens in two ways,

(i) Automatic level is based on habits that rely on schemas in long-term memory which are controlled automatically by stimuli from the environment. This can be seen as any actions that are instinctive or come as second nature.

(ii) Supervisory attention deals with planning and decision making. It creates new strategies when old ones are no longer sufficient. It is also able to consider alternative plans of action and choose the most favorable one.

The Slave Systems, as earlier mentioned consist of,

(i) Phonological loop (Verbal STM) is the auditory component of the STM, which can be further divided into two. 

(a) The articulatory control system (also known as inner voice) can hold information in verbal form) and is also believed to hold words ready for cognitive tasks. 

(b) The phonological store (also known as the inner ear) holds auditory memory traces which can only last for 1.5 to 2 seconds if not rehearsed again by the former system. This store can receive information directly from the sensory memory in the form of auditory material, from LTM in the form of verbal information and from the articulatory control system. This loop has significant implications for a wide range of everyday activities.

Articulatory suppression lends support to the working memory model. Through this, participants are asked to repeat a word while they memorise a list of words. These studies show that such tasks decrease the accuracy of recall of information as the phonological rehearsal system is overloaded.

(ii) Visuospatial Sketchpad is the visual component of the STM (also known as the inner eye). It is the temporary store for visual and spatial information from either the sensory memory or LTM. Visual processing includes storage and manipulation of visual patterns and spatial movements in 2 or 3 dimensions. This system helps one remember what information is important and also where it is.

(iii) The Episodic Buffer temporarily holds several sources (auditory and visual information together as well as information from the LTM) of information active at the same time whilst a person considers what is needed in that situation. The role of this buffer is to act as a temporary and passive display store until information is needed as well as be responsible for our conscious awareness.

A study that explains the STM is the one conducted by Warrington and Shallice (1970), where they carried out a series of tests on patient KF who had suffered brain damage as result of a motorcycle accident. While the patient’s LTM was intact, he showed impairment in his short-term memory and seemed to have problems recalling lists of words and numbers (referred to as his “memory span”) he was able to learn. 

The aim of this study was to investigate the relationship between short-term memory and long-term memory when short-term memory has been impaired. Over the course of it, Warrington and Shallice (1972) found that although he quickly forgot numbers and words when they were presented to him orally, he was able to remember those that had been presented to him visually.

Hence, it was clear that KF’s impairment was mainly for verbal information while his memory for visual information remained more or less unaffected. Therefore, this supports Baddeley’s theory that there are separate STM components for visual information (Visuospatial Sketchpad) and verbal information (Phonological Loop).

This study was also longitudinal in nature, which enabled Warring and Shallice (1974) to become even more precise with their findings. Some of the later testing showed that although the patient could not recall words or letters presented orally, he had no difficulty recalling cat meowings or telephones ringing.

Thus, the researchers concluded that his accident had resulted in damage to a short-term memory store that was auditory and not visual, and further verbal rather than non-verbal. This case study clearly supports the theory that the STM is much more complex than was earlier suggested by the Multi-Store Model of Memory and implies that there are two separate memory stores for verbal/oral information and visual information.

Therefore, we can say that some of the strengths of this model include,

(i) The model is supported by considerable experimental evidence.

(ii) Brain scans have shown that a different area of the brain is active when carrying out verbal tasks than what is used when carrying out visual tasks. This supports the idea that different parts of memory are used for visual and verbal tasks.

(iii) Case studies of patients with brain damage support the theory that there is more than one STM store.

(iv) This model helps one understand why they are able to multitask in some situations and not in others.

That said, like with all models, the WMM comes with some limitations. These include,

(i) The role of central executive is unclear despite it being the most important part of the model according to Baddeley and Hitch. Some examples of this include, that while it has its own limited capacity, it is impossible to measure it separately from the capacity of the phonological loop and visuospatial sketchpad.

(ii) How the various components of the model interest are unclear.

(iii) The model only explains short-term memory, however, it doesn’t tell us much about the processes involved in long-term memory.

(iv) The model does not explain memory distortion or the role of emotion in memory formation.


what about the study to support the model?