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1.
Written and oral spelling were compared in 33 patients with Alzheimer's disease (AD) and 25 control subjects. AD patients had poorer spelling results which were influenced by orthographic difficulty and word frequency, but not by grammatical word class. Lexical spelling was also more deteriorated than phonological spelling. Moreover, oral spelling was more impaired than written spelling in AD patients, whereas no difference was present between oral and written spelling of controls. Analysis of spelling errors showed that, for controls, errors were predominantly phonologically accurate in both spelling tasks. Significantly, AD patients produced more phonologically accurate than inaccurate errors in written spelling, whereas these errors did not differ in oral spelling. In contrast to controls who produced more constant than variable responses in oral and written spelling, AD patients made more variable responses (words correctly spelled in one task but incorrectly in the other) and they showed many instances of variable errors (different misspellings from one spelling task to the other). Two stepwise regression procedures showed that written misspellings were specifically correlated with language impairment, whereas oral spelling errors were correlated with attentional and language disorders. These results suggest that AD increases the attentional demands of oral spelling process as compared to written spelling. This dissociation argues, either for a unique Graphemic Buffer in which oral spelling requires more attentional resources than written spelling or for the hypothesis of separate buffers for oral and written spelling.  相似文献   

2.
In this paper, we report a detailed analysis of the impaired performance of a dysgraphic individual, AD, who produced similar rates of letter-level errors in written spelling, oral spelling, and typing. We found that the distribution of various letter error types displayed a distinct pattern in written spelling on the one hand and in oral spelling and typing on the other. In particular, noncontextual letter substitution errors (i.e., errors in which the erroneous letter that replaces the target letter does not occur elsewhere within the word) were virtually absent in oral spelling and typing and mainly found in written spelling. In contrast, letter deletion errors and multiple-letter errors were typically found in oral spelling and very exceptional in written spelling. Only contextual letter substitution errors (i.e., errors in which the erroneous letter that replaces the target letter is identical to a letter occurring earlier or later in the word) were found in similar proportions in the three tasks. We argue that these contrasting patterns of letter error distribution result from damage to two distinct levels of letter representation and processing within the spelling system, namely, the amodal graphemic representation held in the graphemic buffer and the letter form representation computed by subsequent writing-specific processes. Then, we examined the relationship between error and target in the letter substitution errors produced in written and oral spelling and found evidence that distinct types of letter representation are processed at each of the hypothetized levels of damage: symbolic letter representation at the graphemic level and representation of the component graphic strokes at the letter form processing level.  相似文献   

3.
As a parallel to the dual decoding concept for processing of written language we proposed that phonological encoding does not necessarily occur in writing and that the phonemic and graphemic subsystems can be independent on the one-word level. This hypothesis was tested by comparing oral and written performance in a picture-naming task in Broca's and Wernicke's aphasics. In addition, the residual tacit knowledge of the orthographic properties of the names of the pictures was examined with a multiple-choice recognition task. The principal finding is that Broca's aphasics who were better in written than in oral naming showed more graphemically and semantically motivated errors than aphasics who were better in oral than in written naming, the latter producing more phonemically motivated errors. This result supports the dual encoding concept for writing on the singleword level, implying a direct route from the mental lexicon to the graphemic system in parallel with a route mediated by the phonemic system. Multiple-choice recognition was found to be superior to both oral and written performance in both Broca's and Wernicke's aphasics.  相似文献   

4.
Written spelling deficit of Broca''s aphasics   总被引:1,自引:0,他引:1  
The purpose of this study was to investigate the nature of the written spelling deficit manifested by Broca's aphasics. Four spelling tests were given to eight Broca's aphasic patients. Analysis of misspelling errors led the investigators to conclude that Broca's aphasics do not spell phonically, but rather adhere exclusively to a visual/orthographic strategy. Possible cognitive deficits underlying the spelling problem are identified. The written spelling deficit is related to other features of the syndrome of Broca's aphasia, and finally, speculations are offered concerning the neurological substrate of written spelling in Broca's aphasic patients.  相似文献   

5.
In tests of her ability to produce written and spoken language, this deep dyslexic patient produced semantic, visual, and derivational errors, including functor substitutions, and exhibited part-of-speech and abstractness effects in oral reading, oral and written naming, and writing to dictation, but not in repetition of single words and copying from memory. This patient therefore provides confirmation of the hypothesis presented in Nolan and Caramazza (1982) that the defining symptoms of deep dyslexia will be observed in responses to any task which requires lexical mediation. The patient's written responses in all tasks but direct copying were characterized by spelling errors which included transpositions, omissions, substitutions, and additions of letters. A model of writing is proposed which explains these errors in terms of a disruption of a phoneme-grapheme conversion process which normally functions to prevent decay of information from a Graphemic Buffer.  相似文献   

6.
In a free recall situation, written recall is superior to spoken recall, and evidence is adduced suggesting that this may be partly due to the fact that this method of recall permits greater freedom in ordering the material. Evidence is also adduced suggesting that voicing the material at presentation gives superior recall because of a facilitatory effect on storage. This interpretation is supported by the finding that the advantage of vocalizing is not affected by prior knowledge as to whether recall is to be oral or written, and by the suggestion that vocalized lists are more resistant to intra-trial interference than nonvocalized lists. In addition, two earlier observations were confirmed: first, that the advantage of voicing is most marked at fast rates of presentation; and secondly, voicing gives rise to a higher proportion of acoustic errors relative to the number of items incorrectly attempted.  相似文献   

7.
We present the performance of a patient with acquired dysgraphia, DS, who has intact oral spelling (100% correct) but severely impaired written spelling (7% correct). Her errors consisted entirely of well-formed letter substitutions. This striking dissociation is further characterized by consistent preservation of orthographic, as opposed to phonological, length in her written output. This pattern of performance indicates that DS has intact graphemic representations, and that her errors are due to a deficit in letter shape assignment. We further interpret the occurrence of a small percentage of lexical errors in her written responses and a significant effect of letter frequencies and transitional probabilities on the pattern of letter substitutions as the result of a repair mechanism that locally constrains DS' written output.  相似文献   

8.
A Thai conduction aphasic's performance on a written confrontation naming task is reported. Analysis of his spelling errors indicated that errors rarely violated Thai phonotactic constraints; consonant substitutions were phonologically similar to the target stimuli; longer stimuli were more likely to be in error; distribution of errors was the same across consonants, vowels, and tones; and distribution of error types varied between segmentals (consonants, vowels) and suprasegmentals (tones). Error patterns were similar to those observed in oral reading and repetition. The pattern of impaired writing performance is discussed in relation to a functional model of the spelling process, and it is hypothesized to reflect primarily a functional lesion to the phonological buffer.  相似文献   

9.
The case of an Italian dysgraphic patient (S.E.), who showed a deficit of both written and oral spelling capacities, without significant differences between words and nonwords, is reported. The pattern of the patient's performance was identical on writing to dictation, delayed copying, and written naming. The most common category of errors was single-letter deletions, and errors were predominantly made in medial positions. Stimulus length appeared to be the single factor that most affected performance. This pattern is consistent with the hypothesis that S.E.'s spelling disorder results from selective damage of the Graphemic Buffer. The case is discussed in relation to current functional models of writing and is compared with similar cases reported previously.  相似文献   

10.
11.
We examine methods for measuring performance in signal-detection-like tasks when each participant provides only a few observations. Monte Carlo simulations demonstrate that standard statistical techniques applied to ad’ analysis can lead to large numbers of Type I errors (incorrectly rejecting a hypothesis of no difference). Various statistical methods were compared in terms of their Type I and Type II error (incorrectly accepting a hypothesis of no difference) rates. Our conclusions are the same whether these two types of errors are weighted equally or Type I errors are weighted more heavily. The most promising method is to combine an aggregated’ measure with a percentile bootstrap confidence interval, a computerintensive nonparametric method of statistical inference. Researchers who prefer statistical techniques more commonly used in psychology, such as a repeated measurest test, should useγ (Goodman & Kruskal, 1954), since it performs slightly better than or nearly as well asd’. In general, when repeated measurest tests are used,γ is more conservative thand’: It makes more Type II errors, but its Type I error rate tends to be much closer to that of the traditional .05 α level. It is somewhat surprising thatγ performs as well as it does, given that the simulations that generated the hypothetical data conformed completely to thed’ model. Analyses in which H—FA was used had the highest Type I error rates. Detailed simulation results can be downloaded fromwww.psychonomic.org/archive/Schooler-BRM-2004.zip.  相似文献   

12.
Within the context of a brief experimental design, the current study examined the effects of providing two different types of performance feedback, performance feedback on words read correctly (PFWC) and performance feedback on words read incorrectly (PFWI), on the oral reading fluency of six elementary-aged students. For all of the participants, PFWI resulted in higher levels of oral reading fluency than PFWC. In addition, for a majority of the participants, PFWC resulted in lower levels of oral reading errors than PFWI. These results suggest that providing students with performance feedback on the number or words read correctly may enhance the reading fluency of students experiencing reading difficulties. The implications of these results for intervention selection are discussed.  相似文献   

13.
Most of people′s apparent strategies for covariation assessment and Bayesian inference can lead to errors. However, it is unclear how often and to what degree the strategies are inaccurate in natural contexts. Through Monte Carlo simulation, the respective normative and intuitive strategies for the two tasks were compared over many different situations. The results indicate that (a) under some general conditions, all the intuitive strategies perform much better than chance and many perform surprisingly well, and (b) some simple environmental variables have large effects on most of the intuitive strategies′ accuracy, not just in terms of the number of errors, but also in terms of the kinds of errors (e.g., incorrectly accepting versus incorrectly rejecting a hypothesis). Furthermore, common to many of the intuitive strategies is a disregard for the strength of the alternative hypothesis. Thus, a key to better performance in both tasks lies in considering alternative hypotheses, although this does not necessarily imply using a normative strategy (i.e., calculating the φ coefficient or using Bayes′ theorem). Some intuitive strategies take into account the alternative hypothesis and are accurate across environments. Because they are presumably simpler than normative strategies and are already part of people′s repertoire, using these intuitive strategies may be the most efficient means of ensuring highly accurate judgment in these tasks.  相似文献   

14.
The graphemic buffer and attentional mechanisms   总被引:1,自引:1,他引:0  
Two patients with acquired dysgraphia were reported. The patients' performance in various written and oral spelling tasks converge in support of the hypothesis that they have selective damage, within the spelling system, to the Graphemic Buffer. Although the patients present with comparable patterns of error types, they differ in the distribution of errors as a function of letter position in words. The patients' patterns of errors are compared to previously reported patterns of spelling errors in dysgraphic patients and are discussed in terms of hypothesized mechanisms that operate on the representations that are stored in the Graphemic Buffer.  相似文献   

15.
A method of error analysis, designed to examine phonological and nonphonological reading and spelling processes, was developed from preliminary studies and theoretical background, including a linguistic model and the relationships between articulatory features of phonemes. The usefulness of this method as an assessment tool for phonological ability was tested on a group of normal subjects. The results from the error analysis helped clarify similarities and differences in phonological performance among the subjects and helped delineate differences between phonological performance in spelling (oral and written) and reading within the group of subjects. These results support the usefulness of this method of error analysis in assessing phonological ability. Also, these results support the position that phonological approximation of responses is an important diagnostic feature and merely cataloging errors as phonologically accurate or inaccurate is inadequate for assessing phonological ability.  相似文献   

16.
We assessed whether written task analyses would serve as textual prompts for performing functional tasks by persons with mild disabilities. Several variables that could influence the effectiveness of textual prompts to promote stimulus control were examined across four groups. A consistent finding was that written specific task analyses combined with end-of-trial performance feedback were effective for promoting the acquisition and generalization of several tasks. Performance transferred immediately to natural discriminative stimuli when the written task analyses and feedback were withdrawn for most tasks and participants. For 2 participants, transfer of stimulus control was accomplished by prompt fading, using individualized written task analyses either with or without performance feedback (Group 1). When feedback was not provided, the effectiveness of written specific task analyses was inconsistent across groups. In contrast to the controlling effects of written specific task analyses, written generic task analyses, which specified only major task outcomes, when combined with performance feedback (Group 1) did not control responding. Overall, this research demonstrated the effectiveness of written specific task analyses and performance feedback to promote stimulus control for persons with mild disabilities.  相似文献   

17.
Cognitive analysis of a case of pure dysgraphia   总被引:2,自引:1,他引:1  
An Italian patient with a pure dysgraphia who incorrectly spelled words and nonwords is described. The spelling errors made by the patient were not affected by lexical factors (e.g., frequency, form class) and were qualitatively the same for words and nonwords. The pattern of writing performance is discussed in relation to current models of writing and, specifically, in relation to the role of the Output Grapheme Buffer and Phoneme-Grapheme Conversion in writing.  相似文献   

18.
The aim of this pilot research was to improve understanding of individuals at risk of oral cancer, to determine their attitudes towards and responses to early detection interventions. In-depth interviews with the target group (n?=?25) were used to determine their views, attitudes and requirements for an intervention to encourage early detection of oral cancer. This data was used in combination with theory-based constructs to develop written material that aimed to increase awareness of oral cancer, encourage mouth self-examination (MSE) and early presentation. A second pilot study used a think-aloud protocol to assess the target groups’ (n?=?14) reactions to the written information. In both studies the tape-recorded responses were analysed using framework analysis. The target group had limited knowledge about oral cancer, particularly the signs and symptoms. Participants saw benefits in performing MSE but noted the main barriers were not knowing what signs to look for or where to look. The written information was generally well-received but required some modifications. In particular, the target group required further persuasion that their lifestyle contributed to an increased risk of oral cancer. The results of these pilot studies have informed the development of a theory-based intervention for the early detection of oral cancer.  相似文献   

19.
The main objective of this study is to test a knowledge-based simulation model, elaborated in a previous longitudinal research in order to explain reading errors produced by first-grade children. This model relies on two assumptions: (1) in the beginning of the grapho-phonological acquisition, the child tries to extract, from the series of letters which forms a word, graphic patterns corresponding to an oral syllable; (2) these patterns are stored either in an ordered representation or in a non-ordered representation. Permutation errors, often pointed out in this phase of reading acquisition, would then be the mark of a non-ordered representation of the graphic patterns. Two experiments were proposed to new first-grade children, in the middle of the school year. In experiment 1, they had to detect an oral syllable in written pseudo-words in which the first trigram did or did not correspond to the legal order. In experiment 2, they had to read aloud trisyllabic pseudo-words in which the first trigram was presented in four different orders. Reading errors correspond to the predictions our model allows. Moreover, the absence of correlation between the two tasks suggests that the knowledge activated depends on the type of activity.  相似文献   

20.
Young children can express conceptual difficulties with the appearance-reality distinction in two different ways: (1) by incorrectly reporting appearance when asked to report reality (“phenomenism”); (2) by incorrectly reporting reality when asked to report appearance (“intellectual realism”). Although both phenomenism errors and intellectual realism errors have been observed in previous studies of young children's cognition, the two have not been seen as conceptually related and only the former errors have been taken as a symptom of difficulties with the appearance-reality distinction. Three experiments investigated 3- to 5-year-old children's ability to distinguish between and correctly identify real versus apparent object properties (color, size, and shape), object identities, object presence-absence, and action identities. Even the 3-year-olds appeared to have some ability to make correct appearance-reality discriminations and this ability increased with age. Errors were frequent, however, and almost all children who erred made both kinds. Phenomenism errors predominated on tasks where the appearance versus reality of the three object properties were in question; intellectual realism errors predominated on the other three types of tasks. Possible reasons for this curious error pattern were advanced. It was also suggested that young children's problems with the appearance-reality distinction may be partly due to a specific metacognitive limitation, namely, a difficulty in analyzing the nature and source of their own mental representations.  相似文献   

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