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D Shankweiler

Publications and source records attributed to D Shankweiler.

At least 19 recordsLinked to original sources
PubMed2001

Grammatism.

Findings from the literature on language development, dyslexia, and adult sentence processing provide a vehicle for comparing two models of the symptom complex associated with agrammatism. One model contends that agrammatism represents a deficit in linguistic structures. The other model maintains that the linguistic behavior associated with agrammatism is the result of a limitation in language processing. To adjudicate between the models, the present paper examines one linguistic construction, the restrictive relative clause. The results of experimental investigations across several subject populations reveal parallel patterns of linguistic behavior on this construction. The findings favor the processing limitation account of the linguistic difficulties experienced by agrammatic aphasics in comprehending sentences with a restrictive relative clause.

Aphasia, Broca↗
PubMed2000

An event-related neuroimaging study distinguishing form and content in sentence processing.

Two coordinated experiments using functional Magnetic Resonance Imaging (fMRI) investigated whether the brain represents language form (grammatical structure) separately from its meaning content (semantics). While in the scanner, 14 young, unimpaired adults listened to simple sentences that were either nonanomalous or contained a grammatical error (for example, *Trees can grew.), or a semantic anomaly (for example, *Trees can eat.). A same⁄different tone pitch judgment task provided a baseline that isolated brain activity associated with linguistic processing from background activity generated by attention to the task and analysis of the auditory input. Sites selectively activated by sentence processing were found in both hemispheres in inferior frontal, middle, and superior frontal, superior temporal, and temporo-parietal regions. Effects of syntactic and semantic anomalies were differentiated by some nonoverlapping areas of activation: Syntactic anomaly triggered significantly increased activity in and around Broca's area, whereas semantic anomaly activated several other sites anteriorly and posteriorly, among them Wernicke's area. These dissociations occurred when listeners were not required to attend to the anomaly. The results confirm that linguistic operations in sentence processing can be isolated from nonlinguistic operations and support the hypothesis of a specialization for syntactic processing.

Adult↗
PubMed1998

Anomaly detection: eye movement patterns.

The symptom of a garden path in sentence processing is an important anomaly in the input string. This anomaly signals to the parser that an error has occurred, and provides cues for how to repair it. Anomaly detection is thus an important aspect of sentence processing. In the present study, we investigated how the parser responds to unambiguous sentences that contain syntactic anomalies and pragmatic anomalies, examining records of eye movement during reading. While sensitivity to the two kinds of anomaly was very rapid and essentially simultaneous, qualitative differences existed in the patterns of first-pass reading times and eye regressions. The results are compatible with the proposal that syntactic information and pragmatic information are used differently in garden-path recovery.

Humans↗
PubMed1996

Tasks and timing in the perception of linguistic anomaly.

Three experiments were conducted to investigate the relative timing of syntactic and pragmatic anomaly detection during sentence processing. Experiment 1 was an eye movement study. Experiment 2 employed a dual-task paradigm with compressed speech input, to put the processing routines under time pressure. Experiment 3 used compressed speech input in an anomaly monitoring task. The outcomes of these experiments suggest that there is little or no delay in pragmatic processing relative to syntactic processing in the comprehension of unambiguous sentences. This narrows the possible explanations for any delays that are observed in the use of pragmatic information for ambiguity resolution.

Cognition↗
PubMed1995

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↗
PubMed1995

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↗
PubMed1988

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↗
PubMed1986

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↗
PubMed1985

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↗
PubMed1984

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↗
PubMed1984

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↗
PubMed1983

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↗
PubMed1982

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↗