memory-overview

Introduction

Memory - the ability to store and to recall events, actions and new information is clearly extremely important for all aspects of children’s development. Memory is the storage system for all information and new learning. The human memory system is not fully understood and researchers have described and divided memory in a number of ways, sometimes based on whether the memories are being stored for seconds rather than days (short-term versus long-term memory systems) and sometimes based on the type of information being learned or stored (implicit/explicit, procedural/declarative - implicit or procedural memories are usually memories for skills and habits such as riding a bicycle or playing the piano and explicit or declarative memories are the recall of episodes, events or facts, typically involving verbal recall).

Research into the memory abilities of individuals with Down syndrome has mainly focused on short-term memory. There has been very little research into the long-term memory abilities of individuals with Down syndrome. A limited number of studies suggest that their implicit memory functions better than their explicit memory. [TODO: references 1] This could be because explicit memory usually involves language to a greater extent than implicit memory. Observational reports from parents and teachers suggest that the long-term memory abilities of individuals with Down syndrome, for skills learned and for events recalled, are good. However, this is an area needing more research.

The majority of the research into the memory skills of individuals with Down syndrome has focused on short-term memory abilities and the learning of new tasks. Much of the most recent work published has been based on the working memory model of short-term memory [TODO: references 2]

Aspects of the working memory system seem to be specifically impaired in children and adults with Down syndrome [TODO: references 6] and these impairments could explain much of the difficulty that the children have in learning to talk, in general cognitive development and in learning in some classroom situations. It is possible that, conversely, over time, the speech and language difficulties of many children with Down syndrome limit the development of working memory capacities. It follows, then, that if it is possible to improve the functioning of working memory, this would have a major effect on the speech, language and cognitive difficulties associated with Down syndrome. For this reason, the working memory system is described in some detail in this module.

Drawing on research into the development of working memory in typically developing children, possible ways of improving basic memory function are discussed. Some of these have not yet been tried or evaluated. There have been a number of memory training studies with children, teenagers and adults with Down syndrome that have been published and the outcomes from these are discussed.

In the last section of this module, practical games and activities which may help memory development are described. It is not necessary to understand the research into working memory discussed in the next sections in order to use the practical activities, therefore some readers may wish to go straight to [the practical section].

The working memory system

The working memory system, as conceived by Baddeley and Hitch in Cambridge in 1974, [TODO: references 2]. This model identifies three components, a central executive - the part of the system which processes information, and two temporary stores which are specialised for holding information - the phonological loop for holding verbal information and the visuo-spatial scratch pad for holding visual and spatial information.

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Figure 1. The working memory model [TODO: references 2]

The working memory model has been widely used and has stimulated much research into the development and nature of short-term memory and cognitive processing. Working memory can be thought of as a mental workspace [TODO: references 8] The working memory skills of an individual will, therefore, be very important for supporting such mental activities, for cognitive development and for learning.

In addition, the phonological loop is thought to play an important role in vocabulary learning and may also influence the learning of sentence structures and grammar in early childhood. [TODO: references 4]

The working memory system can be thought of as a child or adult’s ‘gateway’ to the world. The working memory system is in use throughout an individual’s waking hours and the functioning of this system will influence an individual’s ability to make sense of all daily experiences, to understand and remember what is being said to them, to understand and remember what they see, to reason and to learn in the classroom.

The central executive

The central executive is a limited capacity system which is thought to be responsible for a range of cognitive (mental) activities, including the processing and storage of incoming information, the retrieval of long-term knowledge, the control of concurrent processing in the system, and the control of action and planning [TODO: references 3]

The phonological loop

The phonological loop is a limited capacity system which is specialised for the temporary storage of verbal information. Research indicates that verbal information is stored in the phonological loop in its spoken (or phonological) form [TODO: references 3] or aloud.

The visuo-spatial scratchpad

The visuo-spatial scratchpad is a limited capacity system specialised for the temporary storage of visual and spatial information. It has not received as much research attention as the central executive or the phonological loop and is, therefore, less well understood. Recent evidence suggests that it may consist of two systems, one for visual and one for spatial information. [TODO: references 12] However, tasks used to measure the capacity of this system to date have usually required the individual to remember visual items and their spatial locations.

Measuring working memory skills

The capacities of all the components of working memory increase during childhood, and if they do not do so at the expected rate, then this will limit the amount of information that a child or adult can store or process. The measures used to assess the function of each part of the system are described below. The measures described for the phonological loop (verbal short-term spans) and visuo-spatial scratchpad (visuo-spatial short-term spans) have been used in research with children with Down syndrome. To our knowledge, there have not yet been any studies of central executive function in children with Down syndrome.

Measuring verbal short-term memory

Figure 2. Examples of measures of verbal short-term memory (STM)

The capacity of the phonological loop is measured by digit span tasks. In a standard digit span task a child or adult is required to listen to a random list of digits spoken at the rate of one per second, and the individual’s digit span is the longest set of digits that they can recall accurately, in the order in which they were spoken. In childhood, digit spans typically increase from a digit span of 3 at 4-5 years of age to a digit span of 7-8 at 16 years. [TODO: references 13]

The capacity of the phonological loop can also be measured with word lists. The purest measure of phonological loop function may be obtained by using a non-word repetition test designed by Sue Gathercole and colleagues in 1994. [TODO: references 14] This test requires the child to repeat nonwords of varying lengths such as ‘nate’, ‘diller’ or ‘bannifer’ and as these words will not have been heard before, the ability to repeat them will not be influenced by familiarity with the words.

Measuring visuo-spatial memory

The capacity of the visuo-spatial scratchpad is measured by testing the individual’s ability to accurately recall patterns, for example, which squares are filled in a checkerboard or the order in which blocks on a board were touched (the Corsi blocks task) - [see ###### Figure 3.]

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Figure 3. Examples of measures of visuo-spatial short-term memory (STM)

Measuring central executive function

Cats have ears* | “no”
“yes” | | | Counting span | ! | “3, 5, 4” | | | Backward digit span | 8…3…5 | “5…3…8” |

Figure 4. Examples of measures of central executive function

Tasks used to measure central executive capacity usually require both storage and manipulation of information. One such task is the backward digit span task. In this task the child or adult is required to listen to digits as in the digit span task, but to repeat them in the reverse order from the order in which they were spoken. The individual has to be able to store them and reverse the order. Another task used to measure central executive function is a listening span task in which the child may be asked to decide if sentences are correct or not, then to recall the last words of the sentences (see [Figure 4]).

A test designed to measure all three aspects of working memory function for children is about to be published. [TODO: references 15]

Memory development for children with Down syndrome

There has been a significant amount of research conducted into the working memory function of children with Down syndrome in recent years. The research has focused on the phonological loop and visuo-spatial scratchpad, rather than the function of the central executive. This may be because many children with Down syndrome would find the tasks used to assess central executive function rather difficult to understand and to carry out.

The research into the two short-term storage systems has consistently demonstrated that for children with Down syndrome:- [see [TODO: references 6]

• Visuo-spatial short-term memory spans are significantly better than verbal short-term memory spans. For typically developing children the pattern is usually the opposite, with verbal short-term memory spans better than visuo-spatial ones.
• Visuo-spatial short-term memory spans are similar to the spans for typically developing children and other children with learning disabilities of similar non-verbal mental age.
• Verbal short-term memory spans are poorer than the spans for typically developing children and other children with learning disabilities of similar non-verbal mental age.

Working memory for children with Down syndrome

They have a specific impairment in short-term memory for verbal information.

This will make processing verbal information and, therefore, learning from listening, especially difficult for them.

It will also impair vocabulary and sentence learning, so is probably a major cause of their speech and language difficulties.

Their visuo-spatial short-term memory is better than verbal short-term memory.

Their ability to learn from visual information is therefore a relative strength and can be used to support weaker verbal processing abilities

(Non-verbal mental age is estimated by giving children practical tasks to complete which do not require language skills - such as completing jigsaws, and copying block designs or patterns).

A specific impairment in verbal short-term memory

This research indicates that, for children and teenagers with Down syndrome, their verbal-short-term memory spans are smaller than those of children of similar non-verbal mental age, (both typically developing younger children and children of similar age with learning disabilities but not Down syndrome). In fact, as teenagers, individuals with Down syndrome usually have digit spans of 2, 3 or 4 digits while typical teenagers have digit spans of 6, 7 or 8 digits. This difference is significant and will limit the language and cognitive processing abilities of teenagers with Down syndrome in their everyday lives.

The reason for comparing the performance of children with Down syndrome with children matched for mental age measures, is that this information may help to explain the reasons for their difficulties. If they have similar skills to other children of the same mental age, then this would seem to be a pattern of general intellectual delay and it might be assumed that memory skills are in fact progressing as expected. However, if the memory skills are actually lagging behind other mental age measures then it suggests that they are being influenced by some specific difficulties that might be affected by intervention. A number of studies have been designed to try and find out why the verbal short-term memory spans of children with Down syndrome are specifically impaired and the findings are discussed in the next section, which provides a review of the factors thought to influence development in the working memory system.

What influences working memory development during childhood?

Many studies have demonstrated that the capacities of all three components of working memory increase during childhood. There has been more research aimed at understanding the capacity of development in the phonological loop than in the other two parts of the system. [TODO: references 11] Knowledge of the factors that have been found to influence the development of the working memory system in typically developing children may help to identify ways to improve the development of working memory for children and adults with Down syndrome.

A dynamic system

In reading the information on the factors which influence the components of working memory, it is important to remember that it is a dynamic system, developing over time from infancy to adulthood and is influenced by experience and use, as well as by development in other parts of the sensory, perceptual and cognitive systems in the brain.

Influences on verbal short-term span

In typically developing children, the number of verbal items which can be held in the phonological loop increases with age up to about 16 years, with the most rapid change taking place between 3 and 10-11 years. A number of factors are thought to influence the improvement in verbal short-term spans and this information may be important in providing pointers for possible ways of improving phonological loop function. [TODO: references 11]

Auditory discrimination skills and hearing

What influences the development of short-term memory in typically developing children?

Verbal short-term memory capacity increases with age - it is a dynamic, developing system.

Research shows that this increase is influenced by:

• auditory discrimination skills and hearing
• the construction and maintenance of the memory trace in the phonological loop
• the familiarity of the material to be retained
• the ability to reconstruct fading phonological memory traces from stored information
• the ability to retain the items in the order presented
• the ability to retrieve the stored information and to repeat it
• the use of a rehearsal strategy

Any hearing or auditory discrimination difficulties which lead to poor acoustic information being available to the phonological loop would be likely to impair its function. [TODO: references 11] The hearing difficulties which are common in children and adults with Down syndrome may be significantly reducing the acoustic information available.

In recent experimental working memory studies with children and teenagers with Down syndrome, variation in hearing loss has not explained the limited spans of the children. [TODO: references 7] However, even if hearing loss at the time of the study does not relate to variation in performance, hearing loss during preschool years could have had an influence in limiting the auditory information necessary to create an accurate sound pattern for words.

Through their practical work with children with Down syndrome and their families, the authors regularly collect examples to support this view i.e. the 3 year old who uses the same sign for ‘man’ and ‘van’; the same sign for ‘red’ and ‘bread’; the same sign for ‘sauce’ and ‘horse’; though pointing correctly to examples of the two different items. These examples all suggest that the children are hearing only approximations of the words, i.e. “an”, “ed”, “orse”.

Longitudinal studies are needed, which follow children’s development from infancy and monitor their hearing difficulties over time, in order to identify the role that hearing loss plays in all aspects of speech, language and memory development. The levels of hearing loss associated with the conductive loss experienced by the majority of preschoolers with Down syndrome is in the region of 35-45dB. This level of loss will make it difficult for the child to hear the discriminating consonants for words which rhyme, as illustrated by the examples above. If the child cannot hear discriminating consonants, then they will not store accurate representations of the sound pattern of the word (the phonological pattern) in short or long term memory.

In addition, the child will not have accurate sound patterns to support accurate production of the words in speech as they begins to talk. The possible significance of the articulation and phonological difficulties (the unclear speech patterns) that are common in children with Down syndrome do not seem to have been considered in working memory research. If a child cannot hear the sounds or say the sounds clearly, they will have significant difficulty in building a store of accurate and stable phonological (sound) patterns for words. [TODO: references 53].

One study of teenagers and young adults with learning difficulties has demonstrated links between auditory discrimination skills, speech discrimination, speech and language skills and persistent middle ear dysfunction for those with, but not for those without, Down syndrome. [TODO: references 17] The researchers suggest that lower auditory acuity and slower processing speeds both contributed to the poorer performance of the individuals with Down syndrome. In the practical experience of the authors, the minority group of children with Down syndrome who have not had any glue ear or other identified hearing loss have significantly better language comprehension and production skills by 5 years of age and much clearer articulation and phonology than the majority of children with Down syndrome. It would be interesting to know if their verbal short-term memory spans are also better than average.

The construction and maintenance of the memory trace in the phonological loop

Possible reasons for the specific impairment in verbal short-term memory in individuals with Down syndrome

Research suggests that the development of verbal short-term memory may be affected by:

• hearing impairments and poor auditory discrimination skills
• impairments in phonological loop function leading to ‘poor’ phonological representations being constructed and maintained in the loop
• slow development of clear speech leading to ‘poor’ phonological representations being constructed and maintained in the loop
• less familiarity with words, due to slow vocabulary learning and delayed production of words
• being slower to retrieve phonological information from long-term memory
• being slower when organising and saying spoken words
• lack of rehearsal strategies

The ability of the phonological loop to construct and to maintain a memory trace will effect verbal short-term memory skills. [TODO: references 4] concludes that the evidence indicates that the basic function of the loop may be impaired in individuals with Down syndrome and also recommends that research into rates of decay is needed.

There could be two explanations for the apparent impairment in phonological loop function in individuals with Down syndrome. Firstly, it could reflect a biological disadvantage - less effective function in the brain - although it should be remembered that brain functions usually show dynamic development, influenced by input and activity. Secondly, it could reflect the long term effects of the basic speech and language difficulties leading to poorer performance in the phonological loop.

Several studies have established that there is a link between phonological loop function and vocabulary development in typically developing children, and some authors stress that the phonological loop determines the rate of new vocabulary learning [TODO: references 11]

It is likely that both arguments are correct and that both effects are at work over time - illustrating the dynamic nature of development in this system.

The familiarity of the material

There is evidence from a number of studies that the familiarity of the material to be held in the phonological loop influences span scores. [TODO: references 11] Therefore spans will be larger for words or numbers known to the individual than for unfamiliar words or nonwords. This has implications for individuals with Down syndrome as their vocabularies are likely to be small relative to their age and relative to their non-verbal abilities. In addition, even the words that they do know have probably not been listened to or spoken as frequently as they would have been by a typically developing person.

It is likely that the more often a word has been heard, the better the phonological information about that word in long term memory would be, and the better the temporary trace produced in the phonological loop. Similarly, the more often the word has been said by an individual, the quicker they may be in producing the word under test conditions. In addition, the more often the individual has said the word, the more often they may have received feedback to help them improve the accuracy of their stored phonological ‘template’ for the word.

Reconstruction

Linked to the last point, if the words to be recalled are familiar, then the listener may be able to reconstruct a partially decayed trace of the word from their stored knowledge. [TODO: references 11]

The ability to retain the order of the items

All tests of verbal short-term memory require the individual to remember the correct order of the words. Anyone having difficulty with retaining the order information will have smaller span scores. Research with individuals with Down syndrome does not suggest that they have any particular difficulty in retaining the order of the items. [TODO: references 26]

The ability to retrieve and repeat the information

Listening to and repeating words, non-words or digits, requires both storage of the information and the ability to retrieve it. It also requires the individuals to speak the word. The evidence in memory research all indicates that storage and retrieval are separate processes. Information may be stored adequately but there may be impairments in the retrieval process. In addition, someone with speech-motor difficulties may take longer to plan and organise the spoken output of the words, losing some of the information in the process.

There has been some investigation of these issues in relation to individuals with Down syndrome. The time between the researcher saying the last word and the individual starting to repeat the words back is known as the latency period. In some studies this latency period is longer in individuals with Down syndrome, suggesting that it may take them longer to either process the information or organise the spoken response, or both. [TODO: references 28] However, other studies have indicated latency periods which are not longer when compared with appropriate comparison groups. This is an area needing more research.

Rehearsal

At about 7 years of age, children begin to spontaneously rehearse information that has to be remembered either aloud or silently (sub-vocal rehearsal). The speed of this rehearsal process is related to the child’s speech rate. Therefore the increase in speech rate that occurs as children get older explains a large part of the increase seen in verbal short-term memory spans. [TODO: references 4]

Some of the research with individuals (children and teenagers) with Down syndrome indicates that they are able to use rehearsal strategies even though they may not have reached an overall mental age of 7 years. [TODO: references 29] However, their slow speech rate for age will be limiting the benefits of this rehearsal.

Influences on central executive function

To date, there has been no research on the central executive function of individuals with Down syndrome. However, in typical developing individuals, increases in processing efficiency and increases in attentional capacity are thought to explain the increases in central executive capacity. [see [TODO: references 11]

Increases in processing efficiency

The central executive is a limited capacity processing system and its ability to support complex tasks such as processing language during conversations, reading with comprehension or doing mental arithmetic will be influenced by how well the component parts of the tasks are practised or automatised. For example, in reading, if word recognition is well established and words are therefore recognised rapidly without the need to actively decode them, the reader can use more of their working memory capacity to read the text for meaning. Similarly, if multiplication tables are known, these number ‘facts’ to support mental calculations will be available without having to ‘work them out’ and there will be more working memory capacity available to support the rest of the calculation task. Practise of tasks leads to automatisation. For typically developing children, mental and motor skills tend to be practised daily as they are being mastered, so that they become automatised. When a child is acquiring skills more slowly, and each of the skills is more difficult for them to learn and to carry out, then they do not get the level of practise that the typically developing child would have. This lack of practice will lead to a delay in automatising skills.

The result of having to process words for meaning (and to store them) will be to overload the working memory system when trying to carry out tasks such as reading aloud and reading for meaning at the same time. The first author has had the experience of asking a teenager to do this in the course of a reading assessment, and the young man read the passage aloud correctly but could not answer the comprehension questions. However, when allowed to then read the passage over to himself again, he could answer the comprehension questions. This young man had significant speech production difficulties which included a stutter. It seemed that in order to read an unfamiliar passage aloud, accurately and intelligibly, he needed to use all the immediate processing capacity available to him. The author knew, from his classroom performance, that he should have been able to comprehend the material. This experience was a very clear demonstration of the demands of many cognitive tasks on processing capacity. Tasks that typically developing individuals can carry out simultaneously, may create difficulties for children and adults with limited working memory capacities. Teachers may conclude that the tasks are beyond their abilities, but they may not be, if taken one stage at a time.

Increases in attentional skills

The role of attentional skills in increasing working memory capacity has not been extensively explored and is an area that requires research for individuals with Down syndrome. It may be that it is not only the ability to sustain attention that is important, but the ability to switch attention between tasks or manage several aspects of a task simultaneously. Practise and experience of handling more complex tasks with support is important. It may also be important to encourage a child to record each step in the process rather than try to hold them in memory while tackling the next step.

The importance of memory development for children with Down syndrome

The phonological loop and learning to talk

The evidence from research with typically developing children suggests that the phonological loop plays a critical role in learning a spoken language, as it holds the sound pattern for the word to enable the child to store it and to link it to the meaning of the word. If the child cannot hold a clear sound pattern then language learning will be made more difficult. The examples of the children who seem to be unable to discriminate between rhyming words such as ‘van’ and ‘man’ or ‘dolly’ and ‘lolly’ illustrate this point. Children with Down syndrome learn to understand spoken words much more slowly than typically developing children and impairment in the phonological loop may be part of the reason for this. Children with Down syndrome also have difficulty in learning the grammar to understand and build sentences. Research with typically developing children suggests this is also affected by the function of the phonological loop. [see [TODO: references 4]

A number of studies have tried to explore the links between measures of verbal-short term memory and measures of spoken language skills for children with Down syndrome. They report the same findings as the studies of typically developing children. Measures of verbal short-term memory skills seem to be closely related to the expressive language skills of children and teenagers with Down syndrome - that is, more strongly linked with their spoken language ability than their language comprehension. This finding might be expected, as spoken language will be improved by having better phonological information to support speech. [TODO: references 28]

In summary, there is increasing evidence that the functioning of the phonological loop plays a causal role in language learning and in spoken language development in children with Down syndrome, as it does for other children. The implication of this is that if phonological loop functioning can be improved for children with Down syndrome, this will improve their speech and language skills.

Reading, language and memory

Research with typically developing children has shown that learning to read influences the ongoing development of working memory skills. [TODO: references 34]

Table 1. Mean matrices, language and memory scores for readers and non-readers in 1991 and 1995 (raw scores) [TODO: references 36] Reproduced with permission

Table 2. Age equivalent scores for 1995 BPVS and TROG measures for readers and non-readers [TODO: references 36] Reproduced with permission

The children in this study had similar abilities on all the measures at the start of the study, as illustrated in [Table 1]. After 4 years, the non-verbal abilities of the children (Matrices scores) were still no different. Both groups had made the same amount of progress with non-verbal reasoning. However, the children who had received regular, daily reading instruction had made much faster progress in speech, language and memory development. The gains are equivalent to some two years of typical developmental progress - that is, the ‘reading’ children are now two years ahead of their peers who did not receive the same level of reading instruction (see [Table 2]).

The children in this study had all taken part in memory training in the first year of the study. The data in [Table 3] illustrates that the 2 groups of children benefited equally from memory training - see their scores to date. However, those in reading instruction continued to show increase in their memory spans over time, while the training gains were lost for the other children. Memory training is discussed further in the next section.

Table 3. Mean auditory and visual memory scores for readers and non-readers (s.d.s in brackets) [TODO: references 36] Reproduced with permission

This is an example of the dynamic nature of cognitive development and the reciprocal effects of gains in different parts of the system. It would seem that progress in either speech and language skills, or short-term memory skills or reading will each affect the other two in a positive manner.

Research with typically developing children has shown that training them in phonological awareness boosts non-word repetition scores. [TODO: references 37]. All this happens as children learn about phonics as they learn to read and spell in the classroom. Presumably this improves verbal short-term memory as a result of sharpening up the children’s ability to discriminate sounds and to discriminate words, particularly if they are very similar such as ‘man’ and ‘van’. The implication of this is that all work that helps children with Down syndrome to improve their speech sound discrimination skills, right from infancy, will not only help them to develop spoken language but will also improve working memory function.

Memory training for children with Down syndrome

It will be clear from all the evidence discussed above that there are potentially many ways of helping children with Down syndrome to improve their working memory function but few of these have been evaluated. However, one strategy in particular has been tried and that is the training of a rehearsal strategy. Since rehearsal of information definitely helps to retain it, several research groups have set up training studies to evaluate rehearsal training for children, teenagers and adults with Down syndrome

Evidence from training studies

The nature of short-term memory skills for children with Down syndrome

The authors and colleagues began to investigate working memory in children with Down syndrome, and the effects of memory training, in 1991.

In the first study 62 children, from 4 to 18 years of age, completed a battery of memory tests designed to explore their short-term memory skills and some of the children then took part in memory training. [TODO: references 29] The information collected at the start of the study illustrated that, while the visual and verbal short-term memory spans of the children with Down syndrome were small, their short-term memories appeared to function in the same way as in typically developing children.

For example, their performance on verbal tasks indicates that they were using phonological coding. [Table 4] illustrates that the children’s spans for longer, three syllable words were shorter, and [Table 5] illustrates that they found similar sounding words more difficult than dissimilar words.

The word-length effect, the poorer recall of longer words, is taken to reflect the fact that words that have longer phonological patterns will take up more space in the limited capacity phonological loop than short words, so that fewer can be held. The acoustic similarity effect is thought to be due to greater difficulty in discriminating between similar sounding words, as the memory traces in the loop decay.

Table 4. Mean span scores for 1, 2 and 3 syllable words as a function of presentation modality and age [TODO: references 29]] Reproduced with permission

Table 5. Mean span scores for acoustically similar (AS) and dissimilar (AD) words as a function of modality of presentation and age [TODO: references 29] Reproduced with permission

Table 6. Mean digit span scores from the British Ability Scores as a function of modality of presentation and age [TODO: references 29] Reproduced with permission

For the word tasks in this study there were no differences between verbal and visual spans. The visual spans in these tables are spans for spoken words with picture support for each word that the children had to recall. The auditory span tasks required the children to listen to spoken words and repeat them.

[Table 6] illustrates the results for digit span - recall of random numbers. On this task the children did show better spans in the visual than the auditory presentation mode. That is, they did significantly better when they saw the written numerals as well as hearing them, but not when they saw pictures to support words.

A possible explanation of the benefit of visual support for digits but not words is that written digits are very precise and constant images which the children have learned to link to spoken number names. The use of pictures may provide a less efficient aid: while the picture represents the word, the actual picture used (of a dog, or tree, for example) will be new to the child. Printed words might be a more effective support than pictures as they, like numbers, are also precise and constant images for words.

In Tables 4, 5 and 6, the data illustrates that the children’s short-term memory skills are improving with age, albeit slowly. However, the word-length effects and acoustic similarity effects did not change with age, suggesting evidence of phonological coding of the information, but no evidence of a rehearsal effect. Rehearsal starts at about 7 years in typically developing children.

A further interesting finding was the demonstration of a visual similarity effect, that is, the children found that lists of items that looked similar e.g. (ball, wheel, apple, orange), (spade, screw, fork, rake), (television, case, gate, box) were more difficult to remember than lists of items with different shapes (see [Table 7]). This finding suggests that the visual memory mechanisms are being used to support verbal memory. The lack of a verbal memory advantage on any word task, also suggests the children are using visual coding. On all these tasks, typically developing children show better verbal than visual spans. In typical children this is interpreted as evidence for verbal recoding of visual information, i.e. pictures would be named and the names rehearsed to aid visual memory. The authors of the study of the children with Down syndrome suggest that these children may recode verbal information to visual information to aid their poor phonological recording of spoken words. They also suggest that phonologically based training - training speech sound discrimination, and word discrimination - should be evaluated.

Table 7. Mean word span for visually similar (Vis Simm) and dissimilar (Vis Diss) pictures as a function of age [TODO: references 29] Reproduced with permission

(1 syll) | Vis Diss
(2 syll) | | <7 | 0.77 | 1.55 | 1.18 | | 7 - 11 | 1.50 | 2.05 | 1.70 | | >11 | 1.70 | 2.40 | 2.20 |

The benefits of memory training

Several training studies have been carried out in recent years, and have reported similar results. They have all attempted to teach rehearsal strategies to individuals with Down syndrome. In one study, an organisational strategy was also taught; this will be discussed later in the [practical section].

Training studies have all used visual materials, pictures and words, during the training phase, except the most recent one, which is using only auditory (spoken) input. [TODO: references 38] of this module.

The evidence from all the studies is that training can improve both verbal and visual short-term memory spans for children, teenagers and adults. [29-31]

In their studies, the memory training effects were more likely to be sustained when the children with Down syndrome were in mainstream schools and were learning to read. Reading instruction seems to be particularly important. In fact, in the large training study conducted by the authors and colleagues over a four year period, the children’s reading progress was the only significant predictor of memory gains. [TODO: references 40]

[Table 8] illustrates the auditory and visual short-term memory spans for the children who received training and the comparison group, three years after the training. The visual memory spans of the trained group were still significantly better, but not the verbal spans. [Table 9] illustrates the difference between readers and non-readers on the memory measures in 1995. Readers are those children who can read some words on the British Ability Scales Word Reading Scale. Non-readers could not read any of the words. Unfortunately, the majority of the readers were in mainstream placement and the majority of the non-readers in special schools, so the benefits could also be due to being in a better spoken language environment.

Table 8. Auditory and visual short-term memory spans of the trained and comparison groups [TODO: references 40]

group | Comparison
group | Significance | | Verbal mean span | 2.05 | 1.94 | n.s. | | Visual mean span | 2.31 | 1.81* | p = 0.04 |

Table 9. Auditory and visual short-term memory spans of readers and non-readers [TODO: references 40]

There are several possible influences in mainstream schools which may be helping. Firstly, the children have Teaching Assistants (LSAs) and these LSAs actually carried out the memory training so they may have continued practising the activities and consolidating the skills after the training period ended. They may have been alert to the use of the memory skills in classroom learning activities. Secondly, the children in mainstream classrooms receive more intensive reading and writing instruction than their peers in special school and they read and write as they record their work in all areas of the curriculum. Even the children who are not independent readers or writers are helped to record their work in written form by their LSAs. This means that even the children who do not have independent reading and writing skills are exposed to reading and writing daily, and may show benefits from this for speech and language development and memory development. Thirdly, the children with Down syndrome in mainstream schools are in a more stimulating and normal spoken language environment than will exist in many special schools, where most children have speech and language delays.

The effects of inclusion in mainstream schools

Two studies [TODO: references 41]

In a recent paper comparing 22 children with Down syndrome in special schools in a county with almost no inclusion, with 22 in mainstream schools in a neighbouring area of high inclusion, the researcher reports significantly better memory spans for the included children (see [Table 10]). The children in the mainstream schools also had significantly better language skills than the children in special schools even though the two groups did not differ on measures of general non-verbal mental abilities.

Table 10. Auditory and visual short-term memory spans of children in special schools and mainstream education [TODO: references 41]

The differences in grammar comprehension, and visual and verbal short-term memory, between the children in the two school systems remained significant even when age and receptive vocabulary scores were controlled for in the statistical analysis.

Reading ability may have again been a significant factor in the gains achieved in mainstream education, as 20 of the 22 included children could achieve at least a minimal score on the reading assessment, but only 3 of the 22 special school children.

A recent small study reported the positive effects of a computer memory training programme, used over six weeks with children with Down syndrome and other children with learning difficulties in the same schools. Both groups showed steady improvement on the memory tasks on the computer and gains on standardised assessments of memory skills from the British Ability Scales. [TODO: references 43] The children with Down syndrome in the mainstream schools in this study made faster progress than those in special schools even in a six week period. This was possibly because they had more consistent LSA support for the daily training sessions.

These studies emphasise that the benefits of inclusion are significant and produce greater gains for the cognitive development than have been demonstrated for any specific therapy or intervention strategies to date.

Summary

Memory research has demonstrated that:

• Children with Down syndrome have a specific impairment in verbal short-term memory development
• While this may be partly due to hearing, auditory discrimination, and articulation or speech-rate difficulties, there is also evidence of basic impairment in phonological loop function
• The phonological loop is thought to be essential for spoken language learning as it is thought to hold the phonological pattern (sound pattern) of the word as the child learns the meaning of a new word. The phonological pattern of the word will then be stored in long term memory, with its meaning, and be available to guide the spoken production of the word
• Impairment in the phonological loop may explain some of the short-term memory span difficulties which face children with Down syndrome when they are trying to remember two or more items. However, it may also explain at least some of the pattern of speech and language delays and difficulties experienced by most children with Down syndrome, right from infancy
• Activities to improve the function of the phonological loop should be considered as part of memory training activities, as well as activities to improve attention and to increase memory spans

Memory training studies have demonstrated that:

• Children with Down syndrome are using phonological coding but probably not rehearsal strategies as they get older, unless they receive specific training
• Both verbal and visual short-term spans can be improved by teaching children rehearsal strategies
• Visual short-term memory spans tend to improve with training more than verbal spans
• Visual information may be used to support verbal recall tasks and visual recoding of verbal information may be used to aid memory
• The beneficial effects of a few weeks of memory training do not last over time if training or support for memory skills is not maintained
• Children with Down syndrome who are readers have significantly better verbal and visual short-term memory spans. The readers in these studies may only have limited independent reading abilities yet they show substantial memory gains suggesting that being in reading instruction is the important experience. There are many possible reasons for the benefits of reading for memory.

1. Reading, phonics, spelling and writing activities may improve children’s auditory discrimination of speech sounds and their phonological awareness for sounds in words. In turn, this may lead to more accurate phonological representations in the phonological loop.
2. Knowledge and storage of printed words (the visual patterns of words) may provide visual cues to support the storage and retrieval of spoken words (the sound patterns of words) during a memory task. The printed word pattern may prompt recall of spoken words as whole units or provide cues to the specific sounds within the words. Reading activities provide spoken language practice for the children.
3. When their learning support assistants help them to write sentences and record work, the children read aloud and practice grammatically complete sentences at a stage when they are not using such sentences in their spontaneous spoken language. This may help their memory for longer sequences of information.
4. When children with Down syndrome read aloud, their clarity of spoken production improves. This effect is seen even in beginning readers of 3 years of age. Being able to say words more clearly may help to store more accurate phonological patterns for the words in long-term memory.

• Children with Down syndrome who are being educated in fully inclusive schools have significantly better verbal and visual short-term memory spans. The reasons for this could be the positive effects of being in a better spoken language environment, with more speech and language stimulation from other children, greater demands on the children to communicate and higher levels of expectation for language comprehension in the classroom. It could also be the effects of more intensive reading instruction and literacy use in mainstream classrooms, compared with special education classrooms.

This evidence indicates that even if children with Down syndrome have some degree of impairment in basic phonological loop function their short-term memory skills can be improved. More longitudinal research in schools is needed to try and identify exactly how the short-term memory skills are being affected by literacy teaching or by the experience of inclusion.

Implications for activities to improve working memory function

1. Phonological loop impairment: The part of the working memory system that seems to be the most impaired for children with Down syndrome is the phonological loop. This phonological loop impairment will make processing of single words and speech difficult as well as reducing the ability to remember two or more items.
2. Reduced memory spans for lists of items: This results in verbal short-term memory skills that are specifically delayed relative to the children’s non-verbal abilities and to their visual short-term memory skills.
3. Limited central executive capacity: There has been no specific research into central executive function as the tasks used are too difficult for most children with Down syndrome indicating very limited processing capacities. However, research with typically developing children suggests that increasing attentional skills and increasing processing efficiency should help in addition to increasing the storage capacity in the two storage systems.

These findings suggest 3 types of intervention strategies may help to develop the working memory system:

1. Activities to improve phonological loop function
2. Activities to improve remembering of lists of items
3. Activities to improve attention and to increase processing capacity

Suggestions for practical activities are provided for each of these aspects of working memory function in the next section.

Intervention strategies

In this section of the module, we suggest a number of activities which should have an impact on speech, language and working memory development. Most of the activities are based on knowledge of how these systems develop for typically developing children, and the effectiveness of most of the activities for children with Down syndrome needs to be further evaluated.

Mainstream education and reading instruction

The most effective interventions that can be recommended, based on a growing body of consistent evidence from different research groups, is placement in mainstream nursery and school environments and including the children in reading instruction designed to support speech and language learning from an early age.

However, the authors strongly believe, on the basis of many years practical experience and their understanding of the current research evidence, that the activities described below will also enhance the children’s progress.

Reducing hearing difficulties

The first issue to address is hearing. If a child’s hearing is impaired, then they are not going to be able to establish clear phonological representations for spoken words. The majority of preschool children with Down syndrome (at least 80%) have hearing losses, usually due to ‘glue’ in the middle ear. More research into the causes of the ‘glue’ and effective treatments is urgently needed. Grommet surgery and aggressive repeated treatment to keep the ears free of ‘glue’ is recommended by some ENT consultants, but not all. The degree of loss caused by ‘glue’ is about 35-40dB and is considered to be a relatively minor loss by many consultants but not by the authors of this module. This level of loss will affect the ability to discriminate consonant sounds so that ‘man’ and ‘van’ sound the same to the child, similarly ‘hat’, ‘mat’ and ‘cat’. This will seriously impair the child’s ability to learn to talk. Parents need to press consultants to consider treatment with microsuction, grommets and other treatments, and to take this degree of hearing loss more seriously than they often do at present.

Treatment to keep the middle ear clear is not only important for hearing in infancy, there is evidence that the untreated ‘glue’ leads to long term damage in the middle ear. For example, a study of late adolescents and young adults [TODO: references 17] showed some 40% to have permanent dysfunction of the middle ear and no such dysfunction in a comparison group of peers with similar levels of learning disabilities but not Down syndrome. The young people with the middle ear problems showed greater difficulty in discriminating consonants, in recognising words and in speech and language skills.

Hearing aids are sometimes offered for young children, rather than treatments to remove the ‘glue’, but there is no published evidence to support their effectiveness and it is essential to demonstrate that they do, in fact, improve speech discrimination abilities and not just the detection of pure single frequency sounds.

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Figure 5. Examples of a speech sound discrimination game. The child is asked “which one is ‘b’?” or “where is ‘n’?”, using similar sounding pairs. (These cards were designed for preschoolers and the pictures on the cards are a prompt for the sound of the letter, e.g. “ch-ch-ch” for the chugging train, “sh” - the baby is sleeping, “n” for the noise of the sewing machine in action.)

Parents should insist that they are provided with full details of the hearing assessments carried out for their children, that is, copies of audiograms or tympanograms and that they are advised on ways of helping their children to improve their hearing. For example, reducing background noise will help and therefore the television and radio should not be on constantly. Family members and teachers should become conscious of the need to speak clearly, in a loud, clear voice and enunciating consonant sounds at the beginning and ends of words, when talking to a child with hearing loss. Whenever possible, the child should be able to see their face in order to make use of lip shapes and mouth shapes to help them discriminate sounds. Signing is an important aid to understanding new words and to keep children’s comprehension and communication abilities progressing but signing will not help the child’s auditory discrimination skills or the learning of the sound patterns of words. The ability to discriminate and produce speech sounds and words must be encouraged while using signs for infants and for children of all ages.

Activities to improve phonological loop function

Auditory discrimination of speech sounds

Infancy

Right from the first year of life, speech sound discrimination is important. Research indicates that typically developing babies are listening to speech sounds in the language used around them and that they tune their babble to the sound of that language by 12 months of age. There is, therefore, evidence that it is important to begin speech sound work in the first year of life with babies with Down syndrome. This has been recommended by the Swedish speech and language therapist Irene Johansson for many years and her published programme for parents is available in English. [TODO: references 44] This programme recommends that babies have the opportunity to listen to a range of speech sounds and sound combinations, changing them week by week. In addition, parents can be encouraged to play babble games to encourage their children to babble. First, it will help to listen and copy back the sounds the baby is making, then to introduce new sounds and see if the baby will listen to and/or copy the new sounds.

Second year of life

During the second year of life, children with Down syndrome can begin to learn to copy the whole range of speech sounds including consonant and vowel sounds as a game, using Sound Cards [TODO: references 49], or similar materials. Once a child is familiar with the each of the sounds in isolation, they can be asked to discriminate between similar sounds by choosing or pointing to the correct card for the sound.

Preschool

These kinds of games for single speech sound discrimination can continue throughout the preschool stage, encouraging the child to show that they can hear and discriminate sounds and that they can say each of the sounds. There is evidence from research with typically developing children [TODO: references 45] which indicates that their ability to make the sounds determines the rate at which they will try to say words.

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Figure 6. Examples of speech sound discrimination - rhyming words. The child is asked “Can you show me the chair?” or “Which one is the frog?” or “Which one is red?”

School - Primary and Secondary

Once children are in school the materials used for phonics can then be used to teach them to hear and to say all the speech sounds needed for spoken language and for reading and spelling. Many children with Down syndrome in primary and in secondary schools will still not be able to discriminate or to say all the speech sounds, therefore teachers with children in late primary or secondary schools may need to look for phonics materials or for materials from speech and language therapists to support the progress of the children.

Auditory discrimination of words

From infancy to adulthood

The fact that a child or a teenager can hear and say a speech sound in isolation does not mean that the child can always hear that sound in a word or discriminate between rhyming or similar sounding words. Word discrimination games can be played as soon as a child has comprehension for about 50 to 100 words. Young children can be asked to point to objects that have similar names, (such as chair, bear; dog, frog; red, bread) using real objects or pictures, as illustrated in [Figure 6]. Older children can play the same type of word discrimination game, using more advanced, age-appropriate vocabulary.

Auditory discrimination for sounds in words - phonological awareness

Primary and secondary school

The next step is to develop children’s abilities to detect sounds and sound patterns within words. These skills are referred to as phonological awareness abilities. Some typically developing children are able to identify words that rhyme or do not rhyme, or words that start or end with the same sound, when they start school but there is wide variation at this age. Phonological awareness skills generally develop in school over several years, while children are being taught to read.

The benefits of phonics and spelling activities for children with Down syndrome

• most children enjoy the school phonics scheme
• learning a ‘sight’ vocabulary helps children to further understand the letter/sound links - the more words learned by sight, the easier this will be
• makes the sound structure of the language clearer
• learn to identify rhyming words
• learn to segment words into sounds
• learn to ‘blend’ sounds into words
• helps child to discriminate speech sounds within words when listening and talking (phonological awareness)
• will improve verbal short-term memory

In the first year, children do basic phonics work and learn to associate speech sounds with written letters or letter groups. This is important and most children with Down syndrome in mainstream schools enjoy the school phonics scheme and learn letter-sound correspondences. At the same time, all children are learning a ‘sight’ vocabulary, that is, a number of words that they recognise from the pattern of the whole word. This ‘sight’ vocabulary gives all children an important start in reading and provides the child with a database of written words which will help him or her to further understand letter/sound links.

The reason for learning phonics is that knowledge of the letter/sound correspondences enables a child to:-

1. Decode - that is to ‘sound out’ an unfamiliar printed to word in order to try and guess what the word is.
2. Spell - to think how to spell a word by thinking how the word is pronounced.

Children’s abilities in phonological awareness tasks increase steadily in their first few years in school and are greatly helped by reading, writing and spelling activities. As children learn to spell rhyming families such as ‘hat’, ‘mat’, ‘cat’, ‘sat’ the sound structure of the language becomes clearer to them. They can then identify rhyming words such as ‘ring’, ‘string’ and ‘thing’.

They become able to ‘segment’ words into their separate sounds e.g. cat into c-a-t, and to ‘blend’ sounds to make a word e.g. c-a-t- is cat. Segmenting and blending tasks are usually included in batteries of phonological awareness tests, which also include rhyming tasks, and tasks which require the child to identify the ‘odd one out’ for word sets such as ‘man’, ‘van’, ‘hat’. Even more difficult are phoneme deletion tasks such as “What is blend without the ‘b’ (=lend) or swing without the ‘s’ (=wing)?”

The reader will see that all these phonics and spelling activities associated with learning to read will help any child to discriminate speech sounds within words more effectively when listening and when talking, in addition to their benefits for reading and writing.

Summary

The advice is to include children with Down syndrome in all class reading and spelling activities and to develop their sound discrimination, phonic (sounds in print) and phonological awareness (sound in speech) skills, whatever their age. In addition, their articulation and speech production needs can be targeted alongside or within their reading work.

At home and in the car, games like “I spy something beginning with ‘t’’’ can be played, when the children have sufficient understanding of initial sounds in words.

It is probable that many adults with Down syndrome will benefit from targeted speech sound discrimination, word discrimination and speech production activities, in order to improve their listening abilities and their intelligibility when talking.

Activities to improve attention and to increase processing capacity

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Figure 7. Examples of choosing for group activities

Activities to improve children’s attention can begin very early and should continue throughout the school years. For example, playing face-to-face babble games encourages extended periods of attention for babies, as do all early games. In the second and third years of life, attending to teaching games which require sitting still and following instruction are important, first one-to-one with an adult and then as part of a group. In a group, the child has to learn to attend to the ‘teacher’ and to wait until it is their turn. One research study demonstrated better attention skills in children who had attended preschool language groups which provided this type of experience. [TODO: references 48] Reading books with an adult is another activity which many children enjoy and which can be used to extend the periods when they will sit still and concentrate on a task.

Many children with Down syndrome do not have attention difficulties, but some do and they may become apparent quite early. If a child is unable to develop meaningful play and tends to get into wandering, climbing or generally aimless behaviour, it is very important to play with that child and to teach them how to play.

Increasing attention in situations which require the child to process information and to learn to share attention can begin early with simple choice tasks. The number of items offered for the child to make a choice can start at two and then increase to three or four. The child can be asked to choose one item at first and then to choose two. [Figure 7] shows two examples of choosing activities which can be used in groups with children from 18 months of age. For the music session, a child can be asked to choose maracas or bells (both placed in front of child), then the whole group picks up the same one from their own pair for the next game. Similarly, each child could choose a nursery rhyme from picture cards made to depict the rhymes that the children know.

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Figure 8. Hiding game

At home, meaningful choices can be encouraged from the second year of life, especially at mealtimes. A child can be asked “Would you like juice or milk?” or “Would you like a biscuit or a cake?”, with both items in front of the child, who can then indicate their choice by pointing, signing or naming the item.

Activities to improve remembering lists or numbers of items

Preschool

Games to help children to remember two or more items can begin in preschool years and follow on from the simple choice activities described above.

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Figure 9. “What’s gone?” game

Hiding games can be introduced in the second year of life by hiding items under a cloth - first one item, then two and asking the child what is hidden ( [Figure 8]) or by removing one object and leaving the others, again asking the child what has gone ( [Figure 9]).

Primary and secondary school

Simple memory games can be extended for older children using objects or picture materials. At present many teenagers only have short-term spans for 3 or 4 items when using pictures and maybe only 2 or 3 items if asked to remember spoken words. However, school age children will be helped by explicit rehearsal training.

Rehearsal training

Activities designed to teach children to remember items in the order they were given is known as rehearsal training. This has been the activity used in published memory training studies. The steps are illustrated in full in [Figure 10] and [Figure 11]. Start with only one item, then progress to two. Add another item once the child is confident with a list of two items.

1. Turn one over and name (“ball”). Child repeats “ball” (with prompt while learning).

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2. Point and remember: “what was it?” Child says “ball” (prompt with answer while learning).

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3. Turn two cards over and name both in order (“ball”, “boat”).

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4. Point to each of first two cards in order and say “what was it?” Child says “ball”, “boat” (prompt with correct answers while learning).

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5. Show and name three items: “ball”, “boat”, “drum”.

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6. Point to each of the three cards in order and say: “what was it?”. Child says “ball”, “boat”, “drum” (prompt with correct answers while learning).

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Figure 10. Rehearsal shown with picture cards

1. Turn one over and name

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2. Point and remember: what was it?

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3. Turn two over and name

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4. Point and remember: what was it?

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5. Show and name three items

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6. Point and remember: what was it?

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Figure 11. Rehearsal with ‘lift the flap’ chart. The flap-chart and cards illustrated above were produced for the University of Portsmouth memory training research studies discussed earlier in the module. [29,30]

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Figure 12. Rehearsal with language cards

Begin each new session with a sequence of a length that the child was able to remember easily at the previous session rather than starting with a more difficult sequence, and only use a list one item longer than the list the child can consistently succeed on. Remember that, in typical development, it may take two years to add an item to a short-term memory span.

Variations of the task

Once the child has understood the basic procedure and is making some progress, you can include the following variations of the rehearsal task.

Numbers

Make up some cards with numbers on. Use the number cards to encourage remembering longer sequences of numbers. You can use single digits and, for children who know them, some higher numbers.

You can use this method to teach counting by putting numbers in sequence e.g. (1-5) (5-10) (11-15) (16-20) or to teach adding in ‘2’s’ or ‘5’s’ as illustrated in [Figure 13]. You can also use it to teach your child to remember a telephone number.

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Figure 13. Rehearsal for learning to count in 5’s

Words and sentences

For children who can read, the rehearsal game can be used to encourage accurate remembering of short phrases or sentences. Children with Down syndrome, when asked to repeat a sentence, will often repeat only the key words. This task can be used to help repetition of all the words in the phrase or sentence. This may be an effective way to improve your child’s ability to use grammatically correct sentences when they talk. Write each word of a selected phrase or sentence on a separate card and use in the same way as the picture sequences, i.e. by showing one word at a time and gradually increasing the number of words.

Begin very simply, e.g. “the big cat”, and gradually increase the length of the phrase, e.g. “the big cat is sleeping”. Words should be chosen as appropriate for each individual child’s speech and language level and reading vocabulary.

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Figure 14. Rehearsal for spellings

You can also use rehearsal to support spelling activities. Try putting the letters of words that the child is learning to spell on to cards (see [Figure 14]).

In fact, the rehearsal strategy can be used to support any learning activity where remembering a sequence is important: a list of written instructions, the timetable for the day, learning days of the week, months of the year etc.

Other pictures

Using materials that children are particularly interested in will increase their success in learning. If your child has some special interest, say transport or a particular TV programme, find pictures to cut out and use for the rehearsing. Alternatively, you could use photographs of family members and friends. Any activity which requires the child to remember a sequence of words or names can be taught using this rehearsal strategy.

Training auditory rehearsal

All the examples of rehearsal training illustrated so far have used visual prompts to help the child remember the items. It is also important to play games which require listening only, once a child understands the visual rehearsal game, in order to improve auditory and verbal short-term memory. Listening games, when the child has no picture prompts, will be more difficult. However, [Figure 15] illustrates a way of helping a child progress from using visual prompts to hearing and remembering the spoken word: the adult says the name of each item, but the child is able to respond using the pictures. Listening games can be played with lists of words or numbers.

1. Show and name (three) pictures with the child.

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2. Turn the pictures over.

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3. Offer the child a selection of cards, face up.

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4. The child chooses and lines the pictures up in the right position and order.

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5. Turn over the top line and show the child if they are correct.

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Figure 15. Part 1: Moving from rehearsal with picture prompts to auditory rehearsal (Game designed by Leela Baksi of Symbol UK)

1. Place cards face down. Point to each and name it with the child. Do not turn the cards over. The child has to remember the spoken word without a picture prompt.

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2. Offer a selection of cards, face up.

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3. The child places the cards in position. The blank cards help the child remember how many are needed.

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4. The top cards are turned over to see if the child is correct.

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Figure 15. Part 2: Auditory presentation of items to be remembered (Game designed by Leela Baksi of Symbol UK)

Grouping or organisation skills

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Figure 16. Grouping by category, for young children

Grouping items to be remembered by the categories to which they belong is another strategy for increasing the number of items which can be remembered. The aim of this activity is to teach the children to organise and store information in memory by categorising items into groups.

Once the child knows the names of most of the items, you can include some work on grouping in memory sessions.

Sorting task

Begin by selecting pictures or objects from just two categories. Place one item from each category on the table, and then hand the child one item at a time from the remaining items, and ask him or her to find the category that it belongs to. Reinforce the teaching of the appropriate category names as the child places the cards (for example say: “Yes, that’s fruit”). Once the child can manage to sort two categories in this way, increase the number of categories that are to be sorted.

Oddity task

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Figure 17. Grouping by category

This task will draw attention to the groups and reinforce the category names. The child will also learn which item does not belong to a group.

Select all the items from one category and place on the table along with just one item that will be the ‘odd one out’. Look at and name each picture, and say “Which one does not belong?” or “Which one does not belong to the group?”

If there is difficulty in understanding the meaning of “not”, then say (for example): “Show me an animal. Now show me another one, now show me the one that’s not an animal”. If there is still difficulty point to the odd one out and say “Is this an animal?”

Memory task

In this task, unlike the rehearsal memory tasks, you can place less emphasis on remembering the items in correct sequence. The aim is to encourage the child to remember the items in the groups or categories they have been taught.

For example, put some of the animal pictures on the table and point to each one in turn naming the picture and encourage the child to name the picture also. Turn the cards over and say: “Now tell me which pictures you have seen”.

If they cannot remember them all, say “What other animal did you see?”

Try this with other categories.

If the child becomes proficient enough to remember four or five items, you can try using items from two categories at the same time.

Other activities

It is important that the children do not see rehearsal simply as a way of remembering items during the formal training sessions. They should be encouraged to use this strategy as a way of remembering useful lists of items, for example during a game, running an errand or reporting a message. We want the skill to be generalised from the training situation to everyday life. To achieve this, it is important to practice these skills in other situations. Some ideas are listed here.

Delivering messages

Use everyday opportunities for asking the child to deliver messages to others. Ask them to fetch things required from another room, or ask them to pass on messages to other family members, or children in the class if you are working at school. Start with simple messages and make them more complicated as proficiency and confidence increases.

Giving instructions

Opportunities to encourage memory use arise at home and in the classroom whenever a child is being asked to fetch something, point to something, put something away, pick something up etc. Be aware of these opportunities and make use of them to gradually increase the number of items the child is being asked to remember.

Recall of activities

At school, ask the child to recall the events of the previous day or what happened at home the previous evening. At home, ask the child to recall the events of the school day. Try to encourage remembering in sequence by using such prompts as: “And then what happened?”

Recall of stories or nursery rhymes

After reading a story, ask the child to remember the main events of the story in sequence. Some stories, like ‘The Very Hungry Caterpillar’, are especially good for practising the recall of lists of items or events, as they include cumulative lists in the story.

Teach nursery rhymes and songs. Ask questions about the story in the rhyme - being asked to recall the answers may encourage the child to ‘sing’ the lines to himself or herself.

Use of songs

Many children’s songs include sequenced or ordered items. These are very good for teaching sequencing:

Ten Green Bottles; Ten Little Indians; One Potato, Two Potato; One, Two, Buckle my Shoe; Old MacDonald had a Farm; This Old Man; I know an Old Lady who Swallowed a Fly; etc.

Games

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Figure 18. Example of a ‘pairs’ memory game

Most of the activities described can be turned into games, with children taking turns to remember lists of items. ‘Pairs’ memory games can be bought or made (see [Figure 18]). Each child turns over one card, then turns it face down again, and if anyone in the group can remember where the other identical card is, they take the pair. The player with the most pairs at the end of the game is the winner.

Play a game remembering items. The traditional game of remembering an ever-increasing shopping list (I went to the shop and bought a……..) is usually played in a small group but could be played with just one adult and one child. If the child finds it too difficult to add and item to the list, then this aspect can be dropped and only the adult need add an item.

This game can be adapted to all sorts of lists - animals on a farm, animals at the zoo, clothes in the cupboard, toys in the toy-box etc.

Kim’s game

Place a number of small objects on the table. Name each of the objects with the child. Cover them (or get the child to close their eyes) and remove one object. The child must then remember which one is missing. If there is no immediate answer, encourage the child to name the remaining objects - this may prompt the solution. Naming the objects rather than just looking at them encourages the use of a verbal rehearsal strategy for remembering.

Computer games

There is a range of computer programs available for use at home or at school which includes memory games and phonics activities. The memory program used in [the training study described earlier]

Supporting working memory in the classroom

So far, the focus of all the practical advice in this module has been on how to improve children’s memory skills. However, even if these activities do help, children with Down syndrome are likely to have significant difficulty in the classroom where the demand to process spoken language is usually high. Children will be given verbal instructions about the day’s activities and classroom routines. Much of the instruction during lessons will be given verbally. When children with Down syndrome are in an age-appropriate mainstream classroom, the difference between their verbal short-term memory abilities and those of their classmates will be significant.

It is, therefore, important to use as many ways as possible to support the children’s learning by using approaches which do not put an excessive demand on their verbal short-term memory skills.

Visual supports for learning

See also:

• Accessing the curriculum - Strategies for differentiation for pupils with Down syndrome

Information that is illustrated visually, with words, sentences, pictures and symbols through lists, timetables and writing frames can support children’s learning in all aspects of lessons. This includes support for understanding the verbal presentation of information they receive from the teacher, the activities undertaken to promote learning, recording, responding and assessment linked with the aims of the lesson.

Particular styles of lists or writing frames that children understand and can follow can be used repeatedly in a variety of lessons with minor changes to help them access new information, record, rehearse and learn e.g. a story board format.

See also:

• Number skills development for children with Down syndrome (5-11 years)
• Number skills development for teenagers with Down syndrome (11-16 years)

Lists of tasks can be used in maths lessons as well, to practice remembering of a sequence of activities, for example, for addition or subtraction.

Visual presentation is particularly helpful for:

• Developing independent work habits through a list or plan of subtasks the child can follow.
• Increasing the length of time a child can attend and participate in tasks through short activities, clearly illustrated and described.
• Prompting or cueing the child to listen to the teacher’s verbal presentation by providing context.
• Improving behaviour, as expectations can be clearly explained using picture prompts or written instructions.
• Learning and practising new concepts and vocabulary using written words and pictures.
• Understanding and fulfilling the lesson aim by reading the sentences written by an assistant or teacher about the important information of the lesson (in grammatically correct sentences). These sentences will link new vocabulary with familiar vocabulary in sentences, explain meanings, and clearly convey the information the child is expected to understand and learn.

See also:

• Reading and writing development for children with Down syndrome (5-11 years)
• Reading and writing development for teenagers with Down syndrome (11-16 years)

The child will be helped to learn this information by reading back the sentences, reconstructing the sentence(s) through handwritten work, word cards, words on stickers and on the computer and discussing the sentence(s). Most importantly, visual information in the form of pictures, words and sentences, can be used to rehearse information from the previous lesson before continuing with a linked lesson, or to revise a whole topic.

Some techniques used by teachers and assistants for creating dynamic visual records to support children’s memory and help them to learn and remember information (and the language for that information) are listed below.

Visual records to support verbal presentation of information

• Pictures and words will help to focus children’s attention and help them to listen, by providing a context or background for the teacher’s lesson presentation.
• The teacher may use a board and displays as well as verbal presentation.
• Children should have a suitable text book with pictures as well as text to look at (especially in secondary school).
• Some children may need additional pictures and sentences to hold and look at while the teacher is speaking.
• Many children listen to the teacher’s verbal presentation and then immediately rehearse this with an assistant, who can discuss the content, with visual aids, and then list the important points, making clear the tasks required by creating a visual record.
• The assistant can write the aim of the lesson in the child’s record book.

Visual records to support learning activities

Tasks and activities can be described in structured and clear steps in a list or frame, with line drawings where possible to reinforce meaning.

The child can be supported to complete each activity as necessary, and given explicit encouragement to read and rehearse the list, find out what to do ‘next’ and follow the list to completion. The child can tick off or cross through each stage as it is completed.

! ! ! !

For example, as part of a lesson about food at primary school, a child may be asked to:

1. Cut out the pictures.
2. Sort out the pictures into ‘meat’ and ‘fruit’.
3. Stick the pictures into your book.
4. Write the food names underneath the picture.
5. Ask for help to make a sentence: “Cherries are fruit”

Visual records to assist children to record the key points of the lesson

In discussion with the child, the assistant can create an appropriate sentence or several sentences that link with the aims of the lesson. The sentence(s) can include new vocabulary and ideas e.g. “Meat is a type of protein. Protein builds our muscles and helps to make us strong”.

The child can copy write a sentence, either by hand, by using word cards, word stickers, or the computer.

The child can read the sentence(s) back, with help if necessary.

The child can reconstruct the sentence from cards, and verbally.

Visual records to assist children to respond and show their understanding

The aims may be discussed by the assistant and child, using the written record of the lesson.

Can the child answer questions by talking, signing or pointing to pictures or words appropriately, using pictures, sentences, words, lists, storyboards, writing frames, to support assessment?

Can the child generalise the information learned, to apply it in other appropriate tasks? How much help is needed for the child to do this?

Can the child listen to the group discussion and summary by the teacher with the support of a visual record?

Can the child participate in the group or class discussion and answer questions directed at him or her by the teacher?

Summary

These examples of the ways in which visual support can be offered in the classroom have focused on how to assist children to process, remember and record information in all lessons. They provide support for the children’s verbal short-term memory difficulties and their speech and language difficulties.

More information on the ways in which the working memory difficulties of children with Down syndrome can be supported in the classroom during numeracy and literacy lessons are included in the specific practical modules on these topics.

Acknowledgements

The authors would like to thank all the research students and colleagues who have worked with them on working memory research, particularly Professor John MacDonald, now at the University of Paisley, Scotland, and Dr. Glynis Laws, now at the University of Oxford, UK. They would also like to thank the children, parents, teachers and assistants who have participated in the memory training studies.

This module has been improved considerably through discussion with Professor Ben Sacks and his comments on earlier drafts. However, any errors of fact and opinions expressed remain the responsibility of the authors.

Terminology

The term ‘learning difficulty’ is used throughout this module as it is the term currently in common use in the United Kingdom. The terms ‘mental retardation’, ‘intellectual impairment’, and ‘developmental disability’ are equivalent terms, used in other parts of the world.

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