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E Zurif

Publications and source records attributed to E Zurif.

14 recordsLinked to original sources

Processing complexity and sentence memory: evidence from amnesia.

This study examines sentence memory as a function of linguistic processing complexity in amnesic patients. Sentence length as well as lexical and syntactic complexity were manipulated in two sentence repetition experiments. It was found that the amnesic patients performed considerably worse than the control subjects and that performance decreased: (1) when sentence length was increased by the addition of adjuncts compared to arguments of the verb; (2) when the verb selected more thematic frames; and (3) when sentences involved "empty" argument positions that must be linked to antecedents, particularly across clausal boundaries. These data showed how linguistic complexity affects sentence memory and implied that the amnesic deficit did not involve a generalized difficulty for materials of similar length, rather, the deficit was specific to certain representational types and processing routines.

Alcohol Amnestic Disorder

Slowed lexical access in nonfluent aphasia: a case study.

A list priming paradigm (LPP) was used to examine the hypothesis that nonfluent aphasics are literally slowed down in automatic access to lexical information. In this paradigm, words are presented visually, and the subject's task is to make a lexical decision on each word as quickly as possible after its presentation. As soon as a lexical decision is made on one word, that word is removed and, after a predetermined interword interval, the next word is presented. In this way, a continuous "list" effect is obtained. Prior studies with both college-age and elderly subjects using the LPP have shown that, independently of age, on the LPP, priming obtains at interword delays of 500 to 800 msec, but not at either shorter or longer interword delays. In the study reported here, the LPP was used to examine delays at which priming obtained for LD, a nonfluent aphasic with a lesion primarily in the left frontal region. Examining interword delays ranging from 500 to 1800 msec, the subject showed priming only at a delay of 1500 msec, a considerably longer delay than that at which neurologically intact subjects have shown priming. Based on these results, it is argued that while automatic access is retained, that access is much slower in a nonfluent aphasic than in neurologically intact elderly subjects. These results are discussed in terms of how slowed lexical access might impact on discourse comprehension.

Aphasia, Broca

Real-time examinations of lexical processing in aphasics.

We argue that the lesion localizing value of disruptions to modular information processing systems emerges most clearly from on-line analyses of processing. In this respect we seek to show that left anterior (but not left posterior) damage causes slowed information access and we discuss the manner in which this slowing might yield some of the specific syntactic limitations charted in Broca's aphasia. The general possibility we raise is that the cortical area implicated in Broca's aphasia is not necessarily the locus of syntactic representations, but rather sustains particular time-based operating characteristics that in turn sustain normal real-time parsing.

Aphasia, Broca

The time course of automatic lexical access and aging.

This study addresses the issue of cognitive slowing in the elderly by examining the time course of automatic lexical access. College-aged subjects typically show a brief rise time (300-500 msec) for lexical access. In the present study, we examine whether there are changes in rapid, automatized access routines with age. Elderly and college-aged subjects performed a lexical decision task wherein semantically related words embedded in a continuous list were presented one at a time with a varying (300-1500 msec) inter-word interval. The use of a continuous list, a repeated word, and a very short inter-stimulus interval allowed automatic lexical access to be straightforwardly examined. The elderly subjects showed an onset of automatic lexical access that was similar in time frame to that for college-age subjects. These findings suggest that wherever the locus of age-related slowing may be, it is not in the early, language-specific processing devices that mediate lexical access.

Adult

An evaluation of assumptions underlying the single-patient-only position in neuropsychological research: a reply.

This note challenges the position adopted by A. Caramazza and W. Badecker (1989, Brain and Cognition 10, 256-295) that, since the a priori classification of patients can only be theoretically arbitrary, the basic unit of analysis in cognitive neuropsychology must be the individual patient. We argue that even if there is no prior theory to justify patient classification, this does not preclude group studies; syndromes are what the world gives us--they constrain theory, permitting groups to be formed for research purposes. We also reexamine a particular example of group-based research that was extensively criticized by Caramazza and Badecker. We confront each of their criticisms, and, again, demonstrate the validity of group-based research.

Aphasia, Broca

Grammatical class effects in relation to normal and aphasic sentence processing.

Agrammatic, Broca's aphasic patients, Wernicke's aphasic patients, and neurologically intact control subjects were asked to detect target letters in prose passages and in a scrambled word passage. The targets were embedded, in some instances, in content words (open-class vocabulary items), and in other instances, in function words (closed-class vocabulary items). With respect to the prose passages, both the control subjects and Wernicke's aphasic patients were more apt to notice target letters when they appeared in the open-class items than when in closed-class items; by contrast, the agrammatic Broca's patients showed no vocabulary class detection difference. The Wernicke's patients were not entirely normal, however: Whereas the normal subjects showed a much smaller vocabulary class effect for letter detection in the scrambled condition, the Wernicke's maintained the pattern they had shown in the prose condition. These and other findings obtained on the letter cancellation task are discussed in relation to lexical access mechanisms geared to sentence parsing.

Adult

Critical reading at the sentence level in aphasia.

A sentence-reading test was devised in order to assess the aphasic's ability to detect errors in written discourse. One hundred pairs of sentences, each containing one correct and one erroneous sentence, were presented to the patients, who were required to locate the error in one of the two sentences. So that comprehension in the auditory and visual modalities might be compared, the identical test was administered orally to a subset of the aphasic population. Contrary to expectations, there was no difference in overall scores between patients with anterior and posterior pathology. Anterior patients performed somewhat better on the oral version, posterior patients on the written version of the test. Finally, an examination of errors revealed a regular order of difficulty in sentences which featured contradictions to "real-world" knowlege, irrespective of the locus of brain damage, while the order of difficulty of sentences featuring syntactic deviations differed appreciably, depending on the locus of lesion. An attempt is made to relate these findings to current experimental and clinical knowledge.

Aphasia

Pragmatics in aphasia: crosslinguistic evidence.

Previous research suggests that English Broca's and Wernicke's aphasics retain sensitivity to pragmatic factors governing forms of reference, in particular the ability to choose lexical expressions that convey givenness and newness of information. The present study investigates the generality of this phenomenon across patients and language types. Normal and aphasic speakers of English, German, and Italian described nine picture triplets in which one element varied while the others remained constant. Dependent variables included lexicalization versus ellipsis, pronominalization, and definite and indefinite article use. For a subset of German and Italian patients, data were compared to performance in a biographical interview. Results indicate that (a) the pragmatics of reference are preserved in both Broca's and Wernicke's aphasics, despite syndrome-specific problems in retrieving content words and/or closed-class grammatical elements, and (b) certain language-specific patterns of reference are also preserved, including crosslinguistic differences in subject omission. Differences between picture description and the biographical interview reinforce this conclusion. Evidence for the preservation of pragmatics in aphasis is not surprising in its own right, but evidence for the sparing of language-specific relations among pragmatic, lexical, and morphosyntactic patterns can be used to argue against any strong view of grammatical impairment as a disconnection syndrome and/or a loss of grammatical competence. Instead, these data support theories in which grammatical impairment is viewed as a performance deficit.

Adult