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Biomedical subjects

D Shankweiler

Publications and source records attributed to D Shankweiler.

At least 19 recordsLinked to original sources

Syntactic processing in agrammatic aphasia by speakers of a Slavic language.

It is widely believed that agrammatic aphasics have lost the ability to assign complete syntactic representations. This view stems from indications that agrammatics often fail to comprehend complex syntactic structures, as for example, some types of relative clauses. The present study presents an alternative account. Comprehension by Serbo-Croatian-speaking agrammatic aphasics was tested on four types of relative clause structures and on conjoined clauses. The relative clauses varied in type of embedding (embedded vs. nonembedded) and in the location of the gap (subject position vs. object position). There were two control groups: Wernicke-type aphasics and normal subjects. The findings from a sentence-picture matching task indicated that agrammatic aphasics were able to process complex syntactic structures, as evidenced by their well-above chance performances. The success rate varied across different types of relative clauses, with object-gap relatives yielding more errors than subject-gap relatives in all groups. Each group showed the same pattern of errors: agrammatic subjects were distinguished from Wernicke subjects and normal subjects only in quantity of errors. These findings are incompatible with the view that the agrammatics are missing portions of the syntax. Instead, their comprehension deficits reflect varying degrees of processing impairment in the context of spared syntactic knowledge.

Adult

Comprehension of nonlexical categories in agrammatism.

The focus of the paper is a proposal advanced by Grodzinsky (1984, 1986, 1990) concerning a possible syntactic deficit in agrammatism with respect to nonlexical categories. Eight native speakers of Serbo-Croatian, who presented a clinical picture of Broca's aphasia with agrammatism, were tested. Subjects' sensitivity to traces and their knowledge of the inflectional and determiner system was investigated using a grammaticality judgment paradigm. The processing load was further minimized by use of short sentences that unequivocally exemplified different syntactic violations. These steps led to significant improvement in the performance of agrammatic aphasics, a result that is incompatible with the claim that the content of nonlexical elements is lost in agrammatism.

Adult

Sensitivity to inflectional morphology in agrammatism: investigation of a highly inflected language.

We present the results of a study with six Serbo-Croatian-speaking agrammatic patients on a test of inflectional morphology in which subjects judged whether spoken sentences were grammatical or ungrammatical. Sensitivity to two kinds of syntactic features was investigated in these aphasic patients: (1) subcategorization rules for transitive verbs (which must be followed by a noun in the accusative case; intransitive verbs can be followed by nouns in other noun cases); (2) sensitivity to the inflectional morphology marking noun case. The test items consisted of three-word sentences (noun-verb-noun) in which verb transitivity and appropriateness of the case inflection of the following noun were manipulated. Results of the grammaticality judgment task show that both syntactic properties are preserved in these patients.

Adult

Spoken sentence comprehension by good and poor readers: a study with the Token Test.

Good and poor readers in the third grade (age nine years) were examined on a test of immediate memory for word strings and on a version of the Token Test (De Renzi and Faglioni, 1978) to assess sentence comprehension. The poor readers made more errors than the good readers in recall of word strings and on some Token Test items. Those Token Test items that impose the greatest burden on short-term memory were the most sensitive to reader group differences; syntactic complexity alone did not distinguish the groups. The findings support other indications that poor readers make less effective use of working memory in processing spoken sentences than good readers; they do not indicate a syntactic deficit on the part of the poor readers.

Aptitude

Repetitive naming and the detection of word retrieval deficits in the beginning reader.

The claim has been advanced that children with severe reading disability are generally deficient in word retrieval compared with normal readers. Support for the claim is based largely on studies of rapid naming of repetitively presented pictured objects or other nameable stimuli, a task which is apparently more sensitive to retrieval problems than the confrontation naming of items presented singly. The purpose of this study was to examine whether there is a general relationship between word retrieval speed and reading ability in beginning readers. Although such a relationship has not been detected with confrontation naming, repetitive naming may provide a more sensitive test. Accordingly, second-grade children were required to name as rapidly as possible repeated presentations of five pictured items drawn from a single category. Separate naming tests were made for objects, colors, animals, letters, and words. The results showed that there was no relationship between reading ability and naming times when the test items were selected from sets of objects, colors, or animals, whereas on letters and words, a significant relationship was found. The less-skilled readers were not, therefore, consistently slower in all repetitive naming situations. Instead their word retrieval deficits extended only to the orthographic materials.

Child

Linguistic coding by deaf children in relation to beginning reading success.

The coding of printed letters in a task of consonant recall was examined in relation to the level of success of prelingually and profoundly deaf children (median age 8.75 years) in beginning reading. As determined by recall errors, the deaf children who were classified as good readers appeared to use both speech and fingerspelling (manual) codes in short-term retention of printed letters. In contrast, deaf children classified as poor readers did not show influence of either of these linguistically based codes in recall. Thus, the success of deaf children in beginning reading, like that of hearing children, appears to be related to the ability to establish and make use of linguistically recoded representations of the language. Neither group showed evidence of dependence on visual cues for recall.

Child

Repetition and comprehension of spoken sentences by reading-disabled children.

The language problems of reading-disabled elementary school children are not confined to written language alone. These children often exhibit problems of ordered recall of verbal materials that are equally severe whether the materials are presented in printed or in spoken form. Sentences that pose problems of pronoun reference might be expected to place a special burden on short-term memory because close grammatical relationships obtain between words that are distant from one another. With this logic in mind, third-grade children with specific reading disability and classmates matched for age and IQ were tested on five sentence types, each of which poses a problem in assigning pronoun reference. On one occasion the children were tested for comprehension of the sentences by a forced-choice picture verification task. On a later occasion they received the same sentences as a repetition test. Good and poor readers differed significantly in immediate recall of the reflexive sentences, but not in comprehension of them as assessed by picture choice. It was suggested that the pictures provided cues which lightened the memory load, a possibility that could explain why the poor readers were not demonstrably inferior in comprehension of the sentences even though they made significantly more errors than the good readers in recalling them.

Child

Speech perception and memory coding in relation to reading ability.

Previous work has demonstrated that children who are poor readers have short-term memory deficits in tasks in which the stimuli lend themselves to phonetic coding. The aim of the present study was to explore whether the poor readers' memory deficit may have its origin in perception with the encoding of the stimuli. Three experiments were conducted with third grade good and poor readers. As in earlier experiments, the poor readers were found to perform less well on recall of random word strings and to be less affected by the phonetic characteristics (rhyming or not rhyming) of the items (Experiment 1). In addition, the poor readers produced more errors of transposition (in the nonrhyming strings) than did the good readers, a further indication of the poor readers' problems with memory for order. The subjects were tested on two auditory perception tasks, one employing words (Experiment 2) and the other nonspeech environmental sounds (Experiment 3). Each was presented under two conditions: with a favorable signal-to-noise ratio and with masking. The poor readers made significantly more errors than the good readers when listening to speech in noise, but did not differ in perception of speech without noise or in perception of nonspeech environmental sounds, whether noise-masked or not. Together, the results of the perception studies suggest that poor readers have a perceptual difficulty that is specific to speech. It is suggested that the short-term memory deficits characteristic of poor readers may stem from material-specific problems of perceptual processing.

Auditory Perception

Children's memory for recurring linguistic and nonlinguistic material in relation to reading ability.

Good beginning readers typically surpass poor beginning readers in memory for linguistic material such as syllables, words, and sentences. Here we present evidence that this interaction between reading ability and memory performance does not extend to memory for nonlinguistic material like faces and nonsense designs. Using an adaptation of the continuous recognition memory paradigm of Kimura (1963) we assessed the ability of good and poor readers in the second grade to remember three different types of material: photographs of unfamiliar faces, nonsense designs, and printed nonsense syllables. For both faces and designs, the performance of the two reading groups was comparable; only when remembering the nonsense syllables did the good readers perform at a significantly superior level. These results support other evidence that distinctions between good and poor beginning readers do not turn on memory, per se, but rather on memory for linguistic material. Thus they extend our previous finding that poor readers encounter specific difficulty with the use of linguistic coding in short-term memory.

Child

Reading reversals and developmental dyslexia: a further study.

The pattern of errors in reading isolated words was studied in two groups of children with respect, particularly, to reversals of letter sequence and letter orientation. One group (the Institute group) consisted of children 8 to 10 years old who had been diagnosed "dyslexic" according to medical and psychoeducational criteria. The other (the School group) included all the children in a second-year elementary school class (see Liberman, Shankweiler, Orlando, Harris and Berti, 1971) who fell into the lowest third on a standard test of reading achievement. Although the Institute children were somewhat poorer in word recognition than the backward readers selected purely on psychometric grounds, the groups did not differ significantly in the incidence of reversal errors. Also, for both groups, reversals represented a small proportion of the total number of reading errors. The performance of the two groups differed in two respects: in relation to directional bias in letter reversals and in the presence or absence of a significant correlation between letter-reversing and word-reversing tendencies. It was concluded from this that directional problems do not loom large in importance in most cases of reading backwardness, but may provide an additional source of difficulty for some dyslexic children. Other aspects of the error pattern were remarkably the same for both groups. The bulk of reading errors made by both groups reflect their common difficulties in phonemic segmentation of words in the lexicon, in phonetic recoding, and in mastery of the orthography--difficulties, in short, with linguistic characteristics of words rather than with their properties as visual patterns.

Achievement