How is information maintained and retained in the long term?

Although sometimes we remember information without necessarily rehearsing it, experience from daily life shows that information needs to be constantly updated or refreshed to be available over the long term4. If we do not use or encounter information for a certain length of time, we run the risk of not correctly recalling it or not recalling it at all. It is, therefore, appropriate to explore what the literature says on maintaining information for long term recall and what that might mean for the Quran memorizers. In the account that follows, findings from some seminal works dealing with lifelong maintenance of knowledge will be discussed. 4.3.1 The effect of acquisition conditions on long term retention

Research on the acquisition and retention of knowledge indicates two types of studies: (a) Laboratory studies which measure memory performance up to a few hours only under controlled conditions of acquisition and rehearsal; (b) Naturalistic studies which measure knowledge gained and retained over a long period of time such as several years. As the present study is concerned with retention of text over an extended period of time, I shall therefore only look at naturalistic studies.

Bahrick’s (1984) study of the retention of knowledge of the Spanish language, learnt in high school, over a period of fifty years, has provided some useful insights into the duration and

4_{Individuals may remember information such as prayers, a national anthem or lines from} Shakespeare that they might have learned years ago without rehearsing or recalling them in many years. However, it is important to note that they might be exposed to such information although they may not rehearse it loudly or even subvocally. So, it is possible that individuals may sometimes recall information at long intervals without rehearsal.

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maintenance of knowledge over the long term. Initial learning was gauged in terms of courses attended and grades obtained. Minimal rehearsal was reported during the period of retention. Participants’ memory of Spanish was tested by reading comprehension, tests of recall, and recognition of vocabulary and grammar. The results revealed that participants who had attended more courses and achieved high grades retained the knowledge of Spanish more than those who attended fewer courses or who did poorly in terms of grades, after a 50-year interval. One interesting finding from the study was that over the course of fifty years knowledge suffered from exponential loss for an initial three to six years, after which it stabilized and no major loss was observed for almost thirty years. Bahrick concluded that the amount of knowledge which remains accessible for over fifty years despite little or no

rehearsal and use has entered into ‘permastore’—a term that he used for a very long term memory. According to Bahrick, knowledge that enters the ‘permastore’ and is resistant to forgetting is a result of a depth of original training or learning: retention is determined by acquisition conditions. In Bahrick’s study, however, the amount, and distribution of practice were confounded, that is, those who studied more courses also practised more and over a longer period of time. He, therefore, could not show the influence of these variables separately or their interaction.

In a follow-up study, Bahrick and Phelps (1987) tried to tease apart the impact of the above confounding variables. In a longitudinal study, thirty five individuals were tested after 8 years. They had learnedand relearned 50 English-Spanish word pairs under three retraining conditions, i.e., at 30 days, 1 day, and with no interval. In the no interval condition a new relearning session began without any break immediately after the previous session was completed. Total practice was held constant as all participants were trained for the same number of sessions. Recall was tested by asking them to write the equivalent Spanish words for the 50 English words.

According to the results, the inter-session interval had a great effect on the retention after 8 years. Recall was 15%, 8% and 6% for pairs learnt at 30 days, 1 day, and no interval, respectively. According to Bahrick and Phelps, retention of knowledge is dependent on acquisition conditions, with little impact of rehearsal. Words which are better learnt initially and are accessed at longer intervals make the memory trace more durable than words that are quickly learnt and frequently accessed at shorter intervals. Although participants trained at the 30 days interval retained more in the long run as compared to participants trained at

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shorter intervals, they took more acquisition sessions. The relationship between longer but more acquisition sessions and long term memory has a neurological aspect to it, regarding the most effective way to lay down memories, given how the cells operate. Repeated activation of brain neurons leads to permanent structural changes in neuronal connections. Recalling memories at longer intervals activates, reactivates and strengthens the already established memory route resulting in consolidating the memory trace in LTM (see section 4.1 on how long term memories are laid down). In another longitudinal study, Bahrick et al (1993) investigated the course of acquisition and retention of foreign language vocabulary of four participants. Each participant learnt 300 words (English-French or English-German pairs) in six training conditions with each condition having 50 words. Either 13 or 26 relearning sessions were administered at intervals of 14, 28, or 56 days. Retention was tested after 1, 2, 3, or 5 years of termination of the training. Results showed that longer inter-session intervals and more sessions led to higher long term retention. These two variables, however, affected the long-term recall independently of each other. Thirteen sessions with a 56-day interval yielded retention comparable to 26 sessions with a 14-day interval. Although the longer inter- session intervals slowed down the acquisition of vocabulary, they yielded superior long term retention. On the other hand, words that were learnt at 14-and 18-day intervals, respectively, showed better recall initially, but poorer long term retention. This means that an optimal way to learn vocabulary is to spread learning sessions at longer intervals rather than shorter intervals.

The discussion until now has engaged with the maintenance of language knowledge over the long term, and two factors were identified that result in long term retention of words in a foreign language: initial level of learning, and learning distributed over longer-spaced intervals. The effect, however, is not limited to language acquisition or vocabulary learning, as studies on conservation of knowledge in other fields have also shown similar results. Applying laboratory findings to classroom settings, Pashler et al (2007) argued that learning of many different types, such as acquisition of foreign language vocabulary, solving

mathematical problems, learning from maps, and defining uncommon words benefits from spacing-effect. According to them, longer learning intervals are more effective in terms of retention than the shorter ones.

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Bahrick and Hall (1991) conducted a study on the maintenance of high school algebra and geometry over the life span. One thousand and fifty participants were tested. Memory was tested for: (a) specific facts; (b) general principles; and (c) applying principles to a new situation. Results indicated that when the knowledge of algebra was acquired over a period of several years, using, reusing, and relearning the material, the retention level remained high after 50 years even when no rehearsal was reported during the retention interval. In contrast, those participants who acquired algebra only as one year course showed decrement in memory for the material and performed only at chance level at 50-year retention interval. This, according to Bahrick and Hall, shows benefits of spaced learning, i.e. information learnt over an extended period of time divided into shorter sessions is better retained than

information gathered in massed practice. As explained above, there is a neurological aspect to this, regarding the most effective way to lay down memories. Connections between brain neurons get strengthened when information committed to memory is spread over a long period of time resulting in activation and reactivation of cells because of repetition. If it is the case, as indicated above, that the acquisition condition, i.e. how input is initially acquired, is an important requirement for maintaining knowledge over an extended period of time, then input acquired over longer-spaced intervals over a period of time may result in higher long term recall compared to information acquired in massed practice or over shorter intervals.

4.3.2 The effect of retrieval on long term retention

The account so far has showed that participants trained over longer intervals had a better rate of long term retention as compared to those trained over shorter intervals. It means that someone who can easily recall something over short intervals may learn it less well in the end. This may be related to the recency of presentation and last recall, that is, information may be recalled on the basis of recent encounter as opposed to long term memory. The effect of long intervals at acquisition is, however, only one explanation as far as durability of information is concerned. In this section we will look at another explanation i.e. retrieval. Linton (1975, cited in Baddeley et al 2010, p. 197) tested herself on events from her life at regular intervals over a period of five years. She demonstrated that the more an item was recalled on different occasions the more were its chances of being remembered and lesser its

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vulnerability to forgetting and vice versa. Retention was thus shown to be partly a function of how many times an item had been retrieved on earlier occasions. This means that each time an item is recalled, that becomes the interval to the next recall, not the original time of learning.

Karpicke and Roediger (2008) showed that retrieval is critical to consolidation of

information. They studied the learning of 40 foreign vocabulary items (Swahili-English word pairs in which Swahili was the foreign language) across four conditions: (a) repeated study- test trials; (b) once an item was learnt, it was repeatedly presented but not tested anymore; (c) an item was repeatedly tested but was dropped from the study; (d) once an item was learnt, it was dropped from both study and test. When tested a week later, repeated testing had led to a large positive effect (80%) on recall of the word pairs. Repeated presentation of items

without being tested, on the other hand, had not resulted in long-term retention after a week. It suggests that to find something in memory for yourself results in more effective learning than to passively ‘study’ it. Working hard at recalling information from memory matters in terms of longer term retention: the learner actively processes the information and acts on it as he/she searches for it. Retrieving or producing something in this active fashion compared to passively holding it consolidates the memory trace, by strengthening the neurological pathways. Retrieval also entails attention to and elaboration of information.

The discussion so far underscores that retrieving information intentionally and periodically is an effective and critical strategy in relation to consolidating long- term memories: the more one retrieves and uses the information, the more it is maintained and retained in memory. There is, however, more to the act of retrieval than meets the eye. Periodical retrieval, according to Bjork (1988), is not a neutral event, and rather significantly changes the state of information in human memory compared to computer or tape-recorder memory where the contents remain immutable. Bjork considers retrieval practices as a mnemonic aid where an earlier recall enhances memory on a later occasion. He, however, argues that it is a successful or correct recall of an item on the earlier occasion that leads to its successful recall later. Anderson (2010, p. 197) also observes that it is the correct and complete retrieval of an event each time which is necessary for an accurate recall later compared to an incorrect retrieval based on recollection or reconstruction. However, it is important to note that it’s only

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experiments, where you know the original that enables you to see the effect.With episodic memories of events, of course, it’s hard to tell what has been changed.

Retrieval, however, is believed to be most effective and optimal when spaced at regular but expanding intervals. Retrieval at spaced intervals at successively longer delays leads to optimum rehearsal as compared to massed rehearsal or rehearsal at fixed intervals (Landauer and Bjork 1978). According to Bjork (1988), the best way to access and retrieve information from memory is at a point when the information is on the verge of being lost. Accessing information at expanding intervals, according to him, saves it from disuse and ensures a reliable access to information in long term memory.

From the above account it is clear that the effect of spaced learning is pervasive. It is not only at encoding that the effect is found to impact long term recall but also at retrieval.

Information retrieved at spaced intervals enhances the recallability and arrests the rate of forgetting. This implies that the Quran memorizers, for effective recall, have to acquire and retrieve the Quran over intervals spaced over a long time. I will come to this point in the discussion section of this chapter to examine just what the Quran memorizers might be doing, in terms of repetition and recall, to guarantee long term recall.

In chapter 2, it was argued that in everyday life meaning is retained better than form because that is what we want to remember. But when the demand changes (e.g. memorizing script by actors or memorizing poetry), forms is also remembered for a longer period of time. In other words, the purpose of learning or memorizing plays an important role in determining

retention as well as retrieval/recall of information from memory. In the following section I will discuss evidence how the processing of information at different ‘levels’ might contribute to long term recall.