Working memory was previously called the short-term memory. It mainly refers to the memory that an individual is currently processing. This form of memory is seen to last for less than a minute and is found to be limited in its capacity. To help in better understanding of the concept of working memory, Alan Baddeley had developed the working memory approach. According to this approach, working memory can be considered as the system that is composed of several different parts controlling the information being processed (Baddeley, 2017). This model is based on the assumption that each of this components has their own limited capacity and that each of them is relatively but not entirely independent of the others. His original model comprised of three important components that are the phonological loop, visuo-spatial loop as well as the central executive. Later, the current model that was introduced also contained another important component called the episodic buffer. This assignment would mainly be describing this component and will relate the contribution of this model to memory researches.
The first component is the phonological loop that mainly processes sounds and are responsible for speech-based information. This mainly discusses about the sounds that are processed in the mind of an individual. Studies have found that this component, which had been developed by Alan, help in learning new vocabulary, problem solving, remembering instructions and even solving maths problems. This component again comprises of two sub-components that are called the phonological store and the articulatory process (Berry et al., 2018). The first component helps by holding the information for 1.5 to 2 seconds. The articulatory control process helps by refreshing the information in the phonological store. This component also helps in converting the written material into the phonological code helping it to be registered by the phonological code.
When further researches are done on this concept, it is found that phonological store can be indicated by the presence of the phonological similarity effect whereby individuals are found to be less accurate in repeating sequence of similar sounding words like “MAN CAP CAT MAT CAN” in comparison to dissimilar words like that “PIT DAY COW PEN TOP”. In this instance, research has found that similarity in meaning like that (HUGE LARGE BIG WIDE TALL) had very little effects on immediate recall (Allen et al., 2018). Again, it had been also found that when several trials are made for learning longer list of words like around 10 words, meanings are given more importance by humans and in this case, sound loses its power, consistent with the different systems of short term as well as long-term storage. Interesting evidence suggest that the importance of rehearsal comes from the word length effect. Here, researchers have found that immediate recall of words like “(e.g. REFRIGERATOR UNIVERSITY TUBERCULOSIS OPPORTUNITY HIPPOPOTAMUS)” are found to be more error prone than for the shorter words.
Baddeley and Hitch had also contributed to memory researches by discovering a number of important factors. They were of the opinion that that the memory traces of different items in the short term store would rapidly fade but they could be successfully maintained by saying them constantly to oneself. Longer words take more time say and hence they are more prone to the fading process and hence in such instances more forgetting occur. From this interpretation, modern researchers had found that preventing individuals from saying words to themselves by needing the continuous utterance of a particular item like that of the word “the”, can help in removing the word length effect. From the initial demonstrations and discussion of the word-length effects, several other researchers have proposed more interpretations (Hitch et al., 2018). However, they differ principally in the implications of the effects considering whether items in the short-term store are not remembered by people as a result of the spontaneous decay of the memory trace or that by the disruption from later material.
In the further memory researches, the concept of phonological loop put forward by Baddeley had influenced a number of attempts in stimulating human performance in the verbal STM tasks and thereby had used more-detailed computational models. The first tranche of such of the models had focused on specifying mechanisms to handle information about the serial order of the items (Hu et al., 2016). This aspect was left unspecified in the original account of the loop. These models are seen to agree that serial ordering indeed involves “competitive sequencing”. This is mainly a procedure whereby items remain simultaneously active and compete for serial selection. These models in the later researches were seen to differ principally with respect to nature of the ordering cues that help in determining these activation levels. Recent attempts at these computational modelling have been seen to go further by specifying how the short-term phonological storage system can interact with long term memory (Caeyenberghs et al., 2016). This is indeed an essential step in understanding the role of loop in long-term learning.
Another important component is the visuo-spatial sketchpad. This component is responsible for processing spatial and visual information. It could be fed directly through perception as well as indirectly through a visual image. These components has been fund to help individuals in storing images of objects as well as their locations. This component is also used for navigation. When an individual goes from one pace to that of another, this component is stimulated. It is also activated while an individual engages in different types of activities like that of the various activities as such as puzzles, mazes as well as games. Two important components of the sketchpad are also found (Atkinson et al., 2017). One of them is the visual caches that stores information pertaining to colour as well as visual form. Another component is the inner scribe that helps in rehearsing information from the visual caches and transferring information from the visual cache to that of the central executive. The latter component is also seen to deal with spatial and movement information. They are also involved in the planning as well as execution of the different body movements. Further researches on the component had been done that talks about the creation and maintenance of the visual images together with the occurrences of brain damaged individuals who show on deficit but not the other (Despocito & Postle, 2015). This article suggests that information about space as well as about the objects and their visual characteristics might be stored separately. Further researches had been done on memory based on original model of Baddeley. It seems likely that the sketchpad might also be involved in the storage of movement sequences and this suggests that there remains a capacity for storing kinaesthetic information as well as visuo-spatial information (Paulesu et al., 2017). The presence of similarities between the storage or serial order in the visual as well as verbal memory suggests an analogous process though it is not necessary to be present within the single system.
The third important component is called the central executive. This component is mainly seen to incorporate information from the phonological loop, the visuo-spatial sketchpad, the episodic buffer as well as from long-term memory. However, the present day researchers are still not aware fully about the complexity of this component. However, some of the most important functions that had been proposed by modern day researches to be taking place in the central executive are switching of different types of retrieval plans, elective attention, time-sharing criterion during multi-tasking (Del Angel et al., 2015). Others are the effective suppression of the irrelevant information as well as daydreaming and even temporary activation of long-term memory. However, the modern scientists are of the opinion that not all the functions of this component are fully understood. They are of the opinion that more researches need to be conducted to sufficiently understand what the central executives are capable of.
In the field of memory research, the information that had been yielded by Baddeley had been successfully utilised to further venture and explore the working of this components. One of the studies had stated that although the term “central executive” suggest a single monolithic controller, the researchers feel more likely that this component comprises of an integrated alliance if executive control procedures (Paulesu et al., 2017). They are of the idea that it probably has the capability of focussing attention, dividing attention between two or more tasks and controlling access to long term memory and this remains possible based on one or more types of inhibition. Other scientists had investigated executive functioning further where they have worked in connection with the disruption of following damage to the frontal lobes of the brain. This deficit is called the dysexecutive syndrome. The studies have found that there arise major problems in attention controlling and sometimes-repeated preservation of single action is also noticed (Despocito & Postle, 2015). Other participants had shown to fail in maintaining a goal against distraction. It has been also found that in case of memory, this might result in confabulation especially where an attempt to retrieve the memory included capturing if recall by appropriate associations. This sometimes results in developing false memories.
Another important component is the episodic buffer. It was added to the model that was proposed by Baddeley after about 25 years. It has been found by the modern period researchers where information gathered from phonological loop, visuo-spatial sketchpad, and long-term memory are integrated temporarily (Del Angel et al., 2015). This component is seen to be mainly controlled by the central executive but still it can help in transferring information into as well as out of the long-term store. Present day studies are of the opinion that addition of this component to the model had helped in creating a clearer connection between the working memory as well as the long-term memory (Berry et al., 2018).
From the above discussion, it can be seen that the initial researches that had been done by Baddeley had helped in understanding the important components that make up the working memory system. The three components called the the phonological loop, visuo-spatial loop and the central executive. This had based the foundation of the memory research to the latter researchers who had put forward many new insights into the working memory process. Hence, the present day concept on the topic of working memory can be owed to Baddeley.
References:
Allen, R. J., Hitch, G. J., & Baddeley, A. D. (2018). Exploring the sentence advantage in working memory: Insights from serial recall and recognition. Quarterly Journal of Experimental Psychology, 1747021817746929.
Atkinson, A. L., Baddeley, A. D., & Allen, R. J. (2017). Remember some or remember all? Ageing and strategy effects in visual working memory. The Quarterly Journal of Experimental Psychology, (just-accepted), 1-41.
Atkinson, A. L., Berry, E. D., Waterman, A. H., Baddeley, A. D., Hitch, G. J., & Allen, R. J. (2018). Are there multiple ways to direct attention in working memory?. Annals of the New York Academy of Sciences.
Baddeley, A. D. (2017). The concept of working memory: A view of its current state and probable future development. In Exploring Working Memory (pp. 99-106). Routledge.
Berry, E. D., Waterman, A. H., Baddeley, A. D., Hitch, G. J., & Allen, R. J. (2018). The limits of visual working memory in children: Exploring prioritization and recency effects with sequential presentation. Developmental psychology, 54(2), 240.
Caeyenberghs, K., Metzler-Baddeley, C., Foley, S., & Jones, D. K. (2016). Dynamics of the human structural connectome underlying working memory training. Journal of Neuroscience, 36(14), 4056-4066.
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del Angel, J., Cortez, J., Juarez, D., Guerrero, M., García, A., Ramírez, C., & Valdez, P. (2015). Effects of sleep reduction on the phonological and visuospatial components of working memory. Sleep Science, 8(2), 68-74.
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Hitch, G. J., Hu, Y., Allen, R. J., & Baddeley, A. D. (2018). Competition for the focus of attention in visual working memory: perceptual recency versus executive control. Annals of the New York Academy of Sciences.
Hu, Y., Allen, R. J., Baddeley, A. D., & Hitch, G. J. (2016). Executive control of stimulus-driven and goal-directed attention in visual working memory. Attention. Perception, & Psychophysics. doi, 10.
Paulesu, E., Shallice, T., Danelli, L., Sberna, M., Frackowiak, R. S., & Frith, C. D. (2017). Anatomical modularity of verbal working memory? functional anatomical evidence from a famous patient with short-term memory deficits. Frontiers in human neuroscience, 11, 231.
