«DOCUMENT RESUME ED 363 732 CE 064 960 AUTHOR Fowler, Anne E.; Scarborough, Hollis S. TITLE Should Reading-Disabled Adults Be Distinguished from Other ...»
In short, even if all traditional etiological assumptions about the differences among dyslexic children, disadvantaged children, and slow learning child are correctand it may be premature to claim otherwiseit is nevertheless the case that the older they get, the more reading-disabled children will have in common with other poor readers with regard to reading processes and a host of other problems. Thus, individuals from both groups who continue to have reading problems in adulthood are likely to look very much alike and to seek help in many of the same places. The question is, therefore, whether it is possible or desirable to make differential diagnoses and provide specialized assistance in adulthood. Before addressing that question, however, the development and treatment of reading disability in childhood, as well as recent research on the nature of adult reading disability, will be reviewed in more detail.
TECHNICAL REPORT T193-7C. READING ACQUISITION IN GIILDHOOD
To provide a background against which to interpret the reading processes and cognitive profiles of reading-disabled adults, a brief summary is needed of some important aspects of the extensive research that has been carried out in recent decades on the nature of skilled reading and the process of reading acquisition. The characteristic problems faced by children who have difficulty learning to read are reviewed in the section that follows.
1. PROCESSES INVOLVED IN SKILLED READINGAlthough there are many theoretical issues yet to be fully resolved about how reading is accomplished and how children become skilled readers, there are many points on which the research community is generally agreed. Some of the major terms and ideas pertaining to these issues are introduced.
First, the goal of reading is comprehension. Despite occasional attempts to make this guiding assumption into an issue of controversy, few would disagree that the ultimate goal of reading is to understand written material in order to achieve some purpose.
In other words, people read not to decipher a code, but instead to gain knowledge, to be entertained, and so forth. A good reader is thus someone who readily gains a great deal of information from text. Defining reading comprehension formally can be a complicated issue, given the various contents, structures, and genres of different reading materials and reading tasks. For our purposes, however, it is sufficient to say merely that to comprebend is to obtain desired information by reading a particular text, so that what one has comprehended can be exhibited by paraphrasing or answering questions about what was read.
Second, most contemporary models point to two abilities as the major components of reading: (1) determining which words are represented in print, i.e., word recognition, and (2) understanding the meanings of the words and the propositions conveyed by the phrases, sentences, and higher order structures into which the words are combined, i.e., language comprehension.
Both word recognition and language comprehension are necessary for reading success, and neither alone is sufficient for extracting meaning from print. Furthermore, each of these components involves several elements of skill. Skilled word recognition, for
NATIONAL CENTER ON ADULT LtESRACY 19instance, depends on seeing and identifying letters and spaces on the printed page, understandin'.4 the correspondences between letter sequences, called grapbe.mes, and spoken sounds, called pbonemes, using these regularities to decode printed words into their spoken counterparts, knowing that the written forms of some irregular words do not conform to these grapheme-phoneme correspondence regularities, and applying what one knows about letters, letter-sound relations, and word-specific knowledge to identify words in a rapid and efficient, or automatized, manner.
Skilled language comprehension, on the other hand, depends on knowing the meanings of words, analyzing the syntactic and semantic structures of word combinations, using one's background store of information about the topic being discussed, using logical inferential abilities, and so forth. Both comprehension and word recognition also clearly require such general cognitive capabilities as attention and memory.
Third, although there is agreement that word recognition and oral comprehension are the cornerstones of reading, theoretical models differ with regard to the relative importance and independence of these two components. At one extreme, there are bottom-up models, in which the reading comprehension process exactly parallels the listening comprehension process, such that the only difference between listening and reading is that the latter first requires recognition of printed words (Venezky, 1976). The main challenge in reading acquisition, therefore, is simply to discover how to map printed text onto one's existing oral language system. According to such models, reading instruction should be focused first on developing the skills involved in word recognition and then on promoting speed and fluency of those processes. At the opposite extreme are top-down models, in which word recognition is seen not merely as a one-way process of mapping print onto speech, but is also itself greatly influenced by contextual factors (Goodman, 1967; Smith, 1971). According to this viewpoint, therefore, reading instruction ought to focus not just on decoding in isolation, but on learning to recognize words in context in order to make educated guessesbased on semantic, syntactic, and topic knowledgeas to the identity of particular words.
The arguments raised by theorists at both extremes can be appreciated and incorporated into an interactive view in which word recognition and listening comprehension are seen as largely separablebut to some extent also interactive and interdependentcomponents of reading. This study has been influenced by the view of reading advanced by Gough and his colleagues (Gough & Tunmer, 1986; Hoover & Gough, 1990), who TECHNICAL REPORT T193-7 examined the relative contributions of component skills to explaining developmental and individual differences in reading ability. In an interesting series of studies, these researchers have demonstrated that from 73% (at Grade 1) to 90% of the variance in reading comprehension scores can be accounted for by the combination of lust two factors: how well children can decode (as measured by pseudoword reading), and how well they understand oral language (as measured by the accuracy of responses to questions about stories they heard). Evidence that both decoding and listening ccmprehension are the primary determinants of reading comprehension has also been provided by Singer and Crouse (1981), Stanovich, Cunningham and Feeman (1984), and others.
Moreover, although the independent contributions of lowerlevel word recognition and higher-level oral comprehension to skilled reading account for a great deal of the total variance, Hoover and Gough (1990) also showed that a significant additional contribution to prediction was nevertheless made when an interaction term was included in the analysis, apparently reflecting the several ways that strengths or weaknesses in one component process can hinder or facilitate the operation of the other. Much evidence has accrued regarding these direct and interactive effects of decoding and comprehension on reading, as follows.
2. WORD RECOGNITION AND LISTENING COMPREHENSION IN RELATION
TO EACH OTHER AND TO READING COMPREHENSIONIt should be clear on purely logical grounds that if one cannot identify the printed words on a page, extracting meaning will be virtually impossible. While this basic relationship is easily appreciated, what is sometimes overlooked is the importance of the efficiency with which word recognition is accomplished. Some children, for instance, are able to decode individual words quite accurately, but nevertheless fail to derive meaning from text adequately. One possible reason for this is a lack of automaticity in decoding. If it takes an inordinate amount of time and effort for the child to apply knowledge of grapheme-phoneme correspondences and word-specific memories to identify printed words, the word recognition process will proceed so slowly and in such piecemeal fashion that a good representation of the sequence of identified words may not be established in memory, and therefore not be available for meaningful interpretation. This kind of bottleneck, stemming from inefficient low-level processing, is one important interaction between the major components of reading (Perfetti, 1985; Perfetti & Lesgold, 1977; see also Crain & Shankweiler, 1988; and Shankweller & Crain, 1986).
NATIONAL CENTER ON ADULT LITERACY 21The limitation placed on comprehension by weaknesses in decoding leads to an interesting trade-off function with regard to the relative contributions of the two components to reading comprehension at different levels of ability. As Sticht et al. (Sticht, Beck, Hauke, Kleiman, & James, 1974) observed, as long as decoding is not automatized, reading comprehension performance will lag behind oral comprehension performance because the process of recognizing individual words is so laborious as to impede understanding. As automaticity starts to be achieved, which typically corresponds to about the fourth-grade level of word recognition skill, the reader's cognitive resources are not consumed to such a degree by low-level processing, and there is a shift that Sticht described as from learning to read to reading to learn. Increasingly, therefore, reading and listening comprehension levels would ordinarily become more similar once the bottleneck created by effortful decoding is removed. In sum, as reading skill progresses, there is a shift in the relative importance of the component processes, with word recognition playing a much larger role in determining individual differences during the earlier, rather than later, stages of reading acquisition (Curtis, 1980;
Palmer, MacLeod, Hunt, & Davidson, 1985; Sticht & James, 1984).
Reading comprehension is also limited by listening comprehension abilities, particularly for skilled readers. Clearly, fully accurate decoding of words will not ensure comprehension, and comprehension is virtually impossible unless the material would be comprehensible if it were heard rather than read. (For example, one could read aloud most of the text in Biochemical Abstracts but would understand little of what was read). Like oral comprehension, therefore, reading comprehension will be unsuccessful if the meanings of words are not accessed or known, if syntactic and semantic relationships are inaccurately analyzed, and so forth. Of particular importance is familiarity with the topic being discussed in text (or speech). So-called scbema effects, referring to the facilitation of understanding and processing when material is familiar, have long been recognized in cognitive psychology (Bartlett, 1932). With regard to reading, it is quite clear that an individual's knowledge base can limit or enhance the extraction of meaning from text. In one study, for instance, Pearson, Hansen and Gordon (1979) showed that second graders who had greater domain-specific background knowledge about the topics of particular reading passages exhibited greater comprehension of those passages than did classmates of equivalent IQ and general reading ability who were less knowledgeable about those topics.
TECHNICAL REPORT TR93-7 Another constraint on effective reading comprehension is experience with reading itself. Experienced readers know that there are many kinds of reading material (narrative, expository, and so forth), and that certain forms and conventions are associated with each. Moreover, with experience, one learns that material can be read for different purposes, and that the way one processes the text can be adjusted accordingly. Beginning readers need to learn to recognize these sorts of differences and develop some metacognitive strategies for dealing with them (Brown, Armbruster, & Baker, 1986). For example, children must learn to monitor their comprehension levels, reduce their reading speed if necessary to maintain adequate understanding, increase their speed if the goal is just to skim the text, take notes as an external aid to discovering or retaining the structure of the text, and so forth. As Adams (1990) concluded, true understanding of a text is not automatic but requires critical and inferential thought. Consequently, comprehension is an active and effortful application of one's cognitive resources and will be "only as fruitful as the discipline and effort that the reader invests in it" (p. 142). The top-down application of strategies and background knowledge affects not just oral and written comprehension but also, albeit to a lesser extent, the recognition of printed words. Clearly, when faced with the task of reading a word in isolation, the reader must rely solely on lettersound correspondences and memorized spellings. When words are encountered in connected text, however, the reader can also use the context as a clue to identification. If so, contextually appropriate words are more easily and quickly recognized than incongruous words, as has been demonstrated in many studies (Rumelhart, 1977; Posner & Snyder, 1975; Stanovich & West, 1983).
Children whose decoding skills are still shaky have been found to rely heavily on such contextual cues as an aid to recognizing words, particularly those with irregular spelling patterns (Adams & Huggins, 1985; Gough & Hi Ringer, 1980; Jorm & Share, 1983).