Episodic Buffer

Baddeley and Hitch’s (1974) model, despite accounting for a variety of data, was unable to neatly explain a number of phenomena. According to Baddeley and Wilson (2002), the main problem with the model was that it failed to explain how WM is related to LTM, and how information from different sub-systems of WM is integrated. For example, the memory span for unrelated words is five or six, whereas the memory span for words in a sentence is fifteen or more which is beyond the capacity of the phonological loop (Baddeley 2010). As we saw earlier, this beyond-the-usual storage of words in the phonological loop can be explained in terms of ‘chunking’—the process of chaining together words into a chunk (i.e. a higher unit of information), facilitated by syntactic and semantic information from long term memory (section 3.1). The problem however relates to how WM is connected to LTM so as to make use of this information in laying down permanent long term memory traces.

To explain the relationship between working memory and the LTM, the earlier model was reformulated and a fourth component, i.e., the ‘episodic buffer’ (Baddeley 2000) was proposed. In an experiment, Baddeley and Wilson (2002) showed that severely amnesic patients with a significant phonological loop deficit were still able to have good short term prose recall, exceeding the limit of the loop. According to Baddeley and Wilson, the recall performance of these patients could not be explained in terms of phonological memory as their word span was limited to one or two words, nor could it be explained in terms of support from the LTM, which was impaired in these patients. Their explanation was that information is stored in a ‘buffer’ and an intact executive capacity does the processing on the contents of the buffer (p. 1741).

According to Baddeley (2010), the episodic buffer is a limited-capacity back-up store,

drawing information from different stores and keeps it in the form of an integrated episode in a chronological order, like the memory of a movie scene or a story. Pulling information from different and independent sensory channels is assumed to bind or link features to the objects. For example, perceived features like colour, smell, and size are integrated with objects to

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“allow the world to be perceived as comprising a coherent array of objects” (Baddeley 2000, p. 421).

In the above view, the episodic buffer is assumed to be multi-dimensional in nature, that is, unlike the phonological loop and the VSSP which hold specialized codes, the episodic buffer has the capacity to hold and combine limited information in multi-dimensional or multi- modal code. And precisely because of its multi-dimensionality, the buffer “is capable of acting as a link between the various sub-systems of working memory, also of connecting these subsystems with input from LTM and from perception” (Baddeley 2010, p. 56).

In the light of how the episodic buffer works, will it be possible to say that Quran memorizers make an integrated but concrete (episodic) memory trace of the text on the basis of combined (i.e. multi-modal) representation from information in the phonological and visuo-spatial stores? This question is discussed below.

3.2 Discussion

In this chapter we focused on the structure, processes, and functions of working memory in relation to the Quran memorization. The literature reviewed has indicated the following key findings. In what follows, these findings will be discussed.

 Familiarity with the sound and structure of a foreign language may result in efficient memorization and recall in that language.

 Encoding information at more than one level results in a stronger memory trace as compared to encoding information at one level.

The literature suggested that working memory is a means of acquiring information from sensory channels. Working memory is phonological in nature and only accommodates a limited amount of information which if not rehearsed fades away quickly. It was noted that although the capacity of working memory is normally limited to seven plus or minus two elements of information, it can be increased by organizing information into units of higher order.

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The literature suggests that familiarity with text enables a learner to chunk (i.e. create higher- order units of information) which is vital for efficient memorization: chunking increases processing efficiency. Although it is typically assumed that knowledge of the language system and meaning is necessary for chunking in relation to committing information to memory, it may not be absolutely essential. Chunking can be the result of perceptual relatedness too. Someone who knows nothing at all of the language, except the phonology and/or orthography, is obviously at a disadvantage (in terms of encoding and recall at will) as compared to a proficient speaker who can exploit natural sequential associations inherent in a language to form chunks. One can, however, use other cues to chunk and commit text to memory. Familiarity with the sound and structure of a language may be one such cue. In addition, features such as word-likeness, phontotactic similarity, and frequency of occurrence, also help in chunking and committing text to memory.

Sounds that are chunked ‘meaningfully’ might be easier to articulate than sounds without any pattern. What the Quran text provides is not just irregular ‘words’ but ‘words’ with regularity of sound pattern. Once the learners find a way into the phonology of the language, might it be possible for them to sequence sounds according to the phonotactic structure of the language? They could then store sequences of sounds in a patterned way. Quran memorizers’

memorization might thus benefit if they are already familiar with Arabic phonology and script.

Meanwhile, repetition and rehearsal is the means to keep the information ‘at hand’. For the Quran text to be remembered over short and long periods, memorizers have to engage in constant repetition. However, the literature suggested that the Quran memorizers might support and enhance their short term phonological memory by the visuo-spatial imagery of the text. In other words, they will be mapping sounds of the words onto visuo-spatial details—image, colour, font size and location of the text on the page. This is an important idea, implying that in the absence of linguistic meaning, the visual and spatial information may provide a means to hold text in memory. ‘Meaning’ therefore needs to be broadly defined. That is, semantics derived from lexis and grammar are just one kind of ‘meaning’ that might be able to anchor memory. Quran memorizers might thus use visuals and other features of the text to compensate for linguistic meaning as a hook in memory (see chapters 4 and 6 for more discussion on this).

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The literature also suggests that coding information at several levels leads to a rich representation of the memory trace as the text will then be available in several codes:

phonological/articulatory, acoustic, and visual. All a memorizer has to do is to weave all this information into a unified whole using the episodic buffer and central executive. Given that Quran memorizers have the text available to them in both phonological and written forms and that they also hear themselves while reciting the text, the literature reviewed in this chapter suggests that they will have encoded the text at all these levels to make a multi-modal and detailed memory. Encoding the Quran at multiple levels will enhance the chances of successful retrieval.

However, although the literature suggests that memorizers might buttress/support their fleeting phonological memory by means of visuo-spatial mnemonic hooks, it does not shed light on the blind memorizers’ memory of the text. What do the blind memorizers do to shore up the phonological memory? How do they remember the text in the absence of both

meaning and visual details? To answer these questions we need to ask both sighted and blind memorizers about what they do to memorize and retain the text. Chapter 5 will report on the Quran memorizers’ interviews with regard to their practices of memorization.

When we entered this chapter, we wanted to know how the Quran memorizers might be deploying working memory/phonological memory to help them internalise the entire Quran. What this chapter has suggested is that phonological memory on its own would be inadequate because it is associated with STM. Information encoded phonologically is of limited duration and the quantity of material is very limited. In the next chapter we will approach the issue from the other end. If it is assumed that the Quran text ends up in LTM, how does

information get encoded there, and does Quran memorizing meet the conditions for LTM storage, as typically understood in the research literature?

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Chapter 4