Sea creatures is a test of visual memory, involving spatial and temporal sequences. However, since the stimulus items for Sea creatures can be encoded by use of verbal labels, the part played by verbal memory skills in this task is potentially as great as that played by visual memory. Although auditory-verbal memory is usually regarded as being of greatest significance where literacy skills are concerned (see Mobile phone), there is good evidence that visual memory tasks can also give good indications of dyslexia and literacy difficulties (Awaida and Beech, 1995; Beech, 1997; Singleton, Thomas and Leedale, 1996; Singleton, Thomas and Horne, 2000; Bogon et al., 2014). Hence, in cases of literacy difficulties, it is important for the teacher to know whether the student’s visual memory skills are weak or strong, as these will not only affect the diagnosis but also have implications for subsequent teaching recommendations.
Although working memory is typically conceptualised as being a phonological system subserving speech, a visual equivalent known as the ‘visuo-spatial scratch pad’ has been hypothesised (Baddeley, 1986). This is believed to enable us to keep small amounts of visual information in short-term memory. Stuart, Masterson and Dixon (2000) found that visual memory influences the acquisition of sight vocabulary in children aged 5 who displayed poor graphophonic skills (i.e. those who had not yet acquired the ability to segment words on the basis of their sounds and who displayed little or no knowledge of sound-to-letter mappings). For children with good graphophonic skills, however, no association between visual memory and word learning was found. Visual memory is also essential in rapid retrieval of visual whole-word representations from the mental lexicon by older and more fluent readers when reading text (particularly of irregular words for which a phonic strategy would not be appropriate). Visual memory also comes into play when retrieving visual sequences of letters in the correct order for spelling (again, particularly where irregular words are concerned). Hence visual memory is a key component of literacy development.
A study by Palmer (2000) found that children who maintained a visual representation of words alongside a phonological representation after age 7, were significantly worse readers than those for whom the ability to switch strategies by inhibiting the visual representation had fully developed. Children with good visual memory but poor auditory-verbal memory would not only be expected to find acquisition of an effective phonological decoding strategy in reading rather difficult, but also be inclined to rely for a longer period on visual strategies. This approach is liable to run into trouble as the child’s education progresses and the number of new words with which the child is confronted steadily increases.
Sea creatures also requires careful concentration and good visual attentiveness, since the stimulus items are only displayed for very brief periods of time. Therefore, it is possible for a student to perform poorly on Sea creatures not because of inherent memory difficulties, but because of difficulties with attention. Where this appears to be a serious possibility, teachers should refer to other information about a student in order to resolve the issue, or refer the child to an educational psychologist for further investigation. Students with ADHD who have hyperactive patterns of behaviour may also experience difficulties with Sea creatures because of high impulsivity, which can disrupt the processes of memorisation and recall.
Students with very good scores on Sea creatures (or who show a significantly higher score on this subtest than on Mobile phone) may develop an over-reliance on visual strategies in reading, with a consequent neglect of phonic strategies. Although such students may develop quite a large sight vocabulary and, superficially, may appear to be progressing well in their reading development, this state of affairs is not satisfactory because without adequate phonic skills (that have become fluent through regular use and practice) they are highly likely to struggle in reading later on in education. The teacher can always check the student’s phonic skills by using LASS 8–11 Funny words / Non-words, but this will not reveal whether students are actively applying their phonic skills in text reading. Some students (particularly if they are bright) develop the maladaptive strategy of skipping words in text that they do not recognise immediately and using their common sense to construct the meaning of the text in the absence of the skipped words. Although they may get away with this in the primary classroom, they are likely to find that such a strategy lets them down when they get to secondary school, where they will be introduced to many new, often difficult, words. Teachers should therefore try to prevent this by (a) ensuring that all students have a good working knowledge of phonics, and (b) can apply those phonic skills fluently when reading text. The latter should be apparent when listening to a student read an unfamiliar piece of text aloud. A miscue analysis approach could be adopted, which will help the teacher to identify what type of reading errors the student is making. Fluency in text processing can only be achieved by proper practice in reading: teachers should beware that although students may claim to read regularly (e.g. at bedtime) this may involve reading rather unchallenging material. When reading some children’s stories, for example, it is often much easier for the student to skip words that they cannot recognise and still retain a fairly high level of comprehension. By contrast, reading of non-fiction material and ‘classic’ children’s fiction (which often contains a more sophisticated vocabulary) is more likely to encourage children to decode unfamiliar words. However, the text should not be too difficult for the student to tackle otherwise the activity will become excessively frustrating and counterproductive. Ideally there should be no more than about 5% of words that are unknown to the student. More than that amount will mean that the student is too frequently interrupting text reading processes in order to decode unfamiliar words, with the result that it will be difficult for them to hold the meaning of the passage in memory.