1,721,124 research outputs found
Dyslexia in Chinese: Clues from cognitive neuropsychology
No full textIn this review, we describe a series of cognitive neuropsychological studies of Chinese speaking aphasic patients that reveal subtypes of acquired dyslexia and dysgraphia in Chinese. These subtypes can be understood with reference to a cognitive framework that assumes reading and writing to dictation in Chinese depends on the division of labor between two pathways: a lexical-semantic pathway and a direct or nonsemantic pathway. This framework generates a number of predictions about the types of literacy problems that might be observed in native Chinese speakers who are learning to read and write. We argue that the language environment, and specifically the type of script used to read and write, will play a role in determining the phenotype of dyslexia in Chinese. We conclude that dyslexia in Chinese can be caused by psycholinguistic impairments at multiple levels including orthographic, semantic (morphological), and phonological processing.In this review, we describe a series of cognitive neuropsychological studies of Chinese speaking aphasic patients that reveal subtypes of acquired dyslexia and dysgraphia in Chinese. These subtypes can be understood with reference to a cognitive framework that assumes reading and writing to dictation in Chinese depends on the division of labor between two pathways: a lexical-semantic pathway and a direct or nonsemantic pathway. This framework generates a number of predictions about the types of literacy problems that might be observed in native Chinese speakers who are learning to read and write. We argue that the language environment, and specifically the type of script used to read and write, will play a role in determining the phenotype of dyslexia in Chinese. We conclude that dyslexia in Chinese can be caused by psycholinguistic impairments at multiple levels including orthographic, semantic (morphological), and phonological processing
Acquired dyslexia and dysgraphia in Chinese
No full textUnderstanding how the mappings between orthography and phonology in alphabetic languages are learned, represented and processed has been enhanced by the cognitive neuropsychological investigation of patients with acquired reading and writing disorders. During the past decade, this methodology has been extended to understanding reading and writing in Chinese leading to new insights about language processing, dyslexia and dysgraphia. The aim of this paper is to review reports of patients who have acquired dyslexia and acquired dysgraphia in Chinese and describe the functional architecture of the reading and writing system. Our conclusion is that the unique features of Chinese script will determine the symptoms of acquired dyslexia and dysgraphia in Chinese
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Cognate words picture naming in non-alphabetic languages : evidence from Cantonese-Mandarin bilinguals
No full textThe majority of previous studies on cognate words have found a robust cognate facilitation effect in picture naming using alphabetic languages. Research has also identified that if the cognates do not share phonology or meaning (i.e., false cognate inhibition effect), this effect may become inhibitory. These mixed findings seem to suggest that semantics, phonology and orthography may contribute differently to cognate word processing. In this thesis, two effects, the phonological overlap effect and the orthographical overlap effect were examined independently for the first time by testing picture naming in two non-alphabetic languages: Cantonese and Mandarin. Two types of cognate words were included: cognate and semi-cognate words. The orthography of both cognate and semi-cognate words is shared between L1 and L2, but only cognate words share phonology.
The thesis study included three experiments. In the preparatory experiment, an on-line rating study was conducted, whereby cognate and semi-cognate words with mono-syllabic or bi-syllabic names in Mandarin and Cantonese were rated on word AOA, frequency, picture complexity, familiarity and image agreement. From the preparatory experiments a pictorial-word corpus was selected to use in Experiments 1 and 2. In Experiment 1, Cantonese-Mandarin bilinguals named pictures in the corpus in L1 (Cantonese). By contrasting cognate and semi-cognate word naming latency, the results showed a slowed naming latency for cognate words that was marginally significant. It is argued that this finding reflects a possible inhibitory effect from the difference in stages at which competition occurs and the difference in the cognitive load of that competition for cognate and semi-cognate words. In Experiment 2, Cantonese-Mandarin bilinguals named the same pictures in L2 (Mandarin), showing a similar trend of cognate inhibition effect as that found in Experiment 1, albeit with a smaller magnitude of cognate inhibition.
Taken together, the cognate inhibition effect can be explained by the different stages of cross-language competition that occur for cognate and semi-cognate words in picture naming. The cognitive load of overcoming that competition is larger for cognate than for semi-cognate words.published_or_final_versionSpeech and Hearing SciencesMasterMaster of Philosoph
Language distance & billingual language control : a multimodal neuroimaging study
No full textIt is known that the constant demand for language control that bilinguals experience can shape the functioning and structure of their brains in significant ways. Evidence of such bilingualism-related neuroplastic changes is in line with the notion of experience-dependant neuroplasticity. However, the experience of being bilingual varies – bilinguals differ on the age of bilingualism-onset, relative language proficiency, exposure, immersion etc. Variation in these bilingualism-related factors generates different language control needs, which in turn triggers an adaptive response in the form of neuroplastic changes of functional and/or structural capacity, especially within the language control network.
An important point of variation in the bilingual experience that could also give rise to differing language control needs and drive adaptive changes, is the factor of relative language distance. A reasonable assumption is that the closer a bilingual’s pair of languages are, the greater is the need for managing cross-linguistic interference/conflict between them. The focus of this thesis is to explore how the factor of language distance might influence bilingual language control
and in turn contribute towards bilingualism-related adaptive neuroplasticity. Till date, no study has investigated this.
Two neuroimaging experiments were devised and conducted on three groups of bilinguals, all homogenous in their bilingual profiles except for the factor of language distance: high-distance Cantonese-English (CE), intermediate distance Hindi-English (HE) and low-distance Dutch-English (DE) speakers.
The first study used a translation task to specifically elicit activation within the language control network to uncover adaptive changes in functional activity in the network. The results showed a differential activation of the Anterior Cingulate Cortex (the region implementing conflict control) in the pattern of DE>HE>CE, for identical levels of performance. This suggests that language control regions in bilinguals functionally adapt to different conflict control demands generated by linguistic distance.
The second study was aimed at uncovering whether the experience of managing “close” and “distant” languages had induced any adaptive structural changes in the language control networks of the three representative bilingual groups. The results of this structural imaging study (after controlling for potential confounding variables) showed significant bilateral putaminal volume variation between the groups, along the language distance gradient in the pattern of CE>HE>DE. This is attributable to the differing articulatory control needs generated by language distance. This suggests that experience with managing differently overlapping L1-L2 phonemic repertoires could induce adaptive structural changes.
The above findings provide emerging evidence of how language distance can differentially affect language control demands and bring into effect different
functional and structural adaptive changes within the bilingual language control network. Language distance could be a potential factor that induces important neurocognitive heterogeneity amongst bilinguals, in the way other bilingualism-related variables such as relative language proficiency, L2AoA and immersion/exposure do.
Finally, considering the cross-populational nature of this research undertaking, hitherto unavailable norms in Hindi for a picture stimuli set were collected. The norms were necessary for assessing L1 proficiency of the Hindi-English bilinguals who took part in the study. The availability of norms in several world languages can facilitate cross-populational and cross-linguistic research in bilingualism.published_or_final_versionSpeech and Hearing SciencesDoctoralDoctor of Philosoph
Cognitive screening for impairments following stroke
No full textThe primary motivation for this thesis is to define cognitive impairments following stroke, to assess them in a valid and practical manner, and to discriminate post-stroke cognitive profiles from other types of cerebrovascular disease (CVD).
First, an overview of 33 diagnostic test accuracy systematic reviews is presented to identify the main conditions for the assessment of patients with CVD and the most sensitive screening tools recommended for them. The reviews focused on the detection of cognitive impairment, dementia, and stroke evaluated by DSM guidelines and MCI diagnosed by Petersen criteria. Analyses show that MMSE is recommended for dementia, whereas for MCI and stroke, the most frequently reported tests are MoCA and ACE-R, with OCS also recommended in the recent stroke reviews.
The overview found no reports on tests in Russian. Therefore, the online survey for Russian-speaking clinicians about the preferred methods of cognitive assessment and rehabilitation was conducted. 110 participants reported using MoCA, MMSE, and Luria Neuropsychological Battery for stroke, whereas for dementia, the FAB was also mentioned. These results show some compatibility between Russian and international practices.
Following the overview and survey outcomes, a Russian version of the OCS was developed. The advantages of OCS over MOCA and MMSE are minimal demands on language production, hand movement, and visuospatial processing to increase sensitivity to executive functions, number processing, memory, language, and praxis abilities. After linguistic adaptation, normative data were collected on 60 healthy and 205 post-stroke participants to determine cut-off scores, convergent validity, test-retest reliability, internal consistency, sensitivity, and specificity. Results showed the Rus-OCS had a fair level of psychometric properties allowing to recommend it for further validation and clinical use.
Additional work was conducted to investigate the discriminant ability of the Rus-OCS for patients with stroke (n = 175) and small vessel disease (SVD) (n = 41). The MoCA and Rus-OCS scores were compared in these groups, including the impact of age, gender, education, and the disease duration. The results suggest the use of MoCA as a primary screen to detect cognitive impairment, as it is faster and can discriminate stroke and control groups. However, for the clinical population, the use of Rus-OCS could be more informative, as it can contrast stroke and SVD groups by numerical, visuospatial, and naming subtests together with scores on language and memory domains.
The concluding chapter presents a conceptual framework for stroke education with reference to securing new resources for patient education. A case study of a patient education initiative in Moscow was reported to illustrate this framework. 24 patients participated in the Stroke School for seven weeks. They were assessed with WHODAS.2.0 before and after the intervention and showed improvements in cognition, life activities, participation, and sociability domains. The results demonstrate how an educational initiative in the inpatient clinical settings may enhance the benefits of other rehabilitative interventions, although participants’ learning motivation should be considered.
Overall, the results from this thesis establish a new benchmark for the future research of cognitive assessment and related applications in stroke rehabilitation for Russian speakers.published_or_final_versionEducationDoctoralDoctor of Philosoph
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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