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2.
Neuropsychol Rehabil ; 20(4): 601-23, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20574915

RESUMO

This study examines the reasons for the success of Multiple Oral Re-reading (MOR; Moyer, 1979), a non-invasive, easily administered alexia treatment that has been reported in the literature and is currently in clinical use. The treatment consists of reading text passages aloud multiple times a day. Findings that MOR improves reading speed on practised as well as novel text have been inconsistent, making MOR's role in the rehabilitation of alexia unclear. We hypothesised that MOR's treatment mechanism works through repetition of high frequency words (i.e., bottom-up processing). We designed and controlled our text passages to test the hypothesis that participants would not improve on all novel text but would improve on text that includes a critical mass of the words contained in the passages they were re-reading. We further hypothesised that the improvement would be at the level of their specific alexic deficit. We tested four participants with phonological alexia and two with pure alexia during 8 weeks of MOR treatment. Contrary to the conclusions of previous studies, our results indicate that improvements in top-down processing cannot explain generalisation in MOR and that much of the improvement in reading is through repetition of the practised words. However, most patients also showed improvement when specific phrases were re-used in novel passages, indicating that practice of difficult words in context may be crucial to reading improvement.


Assuntos
Dislexia/fisiopatologia , Dislexia/reabilitação , Linguística , Processos Mentais/fisiologia , Leitura , Ensino/métodos , Idoso , Feminino , Lateralidade Funcional/fisiologia , Humanos , Testes de Linguagem , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Resultado do Tratamento
3.
Phys Rev Lett ; 102(16): 161302, 2009 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-19518694

RESUMO

We constrain parity-violating interactions to the surface of last scattering using spectra from the QUaD experiment's second and third seasons of observations by searching for a possible systematic rotation of the polarization directions of cosmic microwave background photons. We measure the rotation angle due to such a possible "cosmological birefringence" to be 0.55 degrees +/-0.82 degrees (random) +/-0.5 degrees (systematic) using QUaD's 100 and 150 GHz temperature-curl and gradient-curl spectra over the spectra over the multipole range 200

4.
Neuropsychologia ; 40(2): 223-34, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11640944

RESUMO

Patients with phonological alexia (difficulty reading pseudowords) frequently have concomitant difficulty reading functor words and verbs compared with concrete nouns. The current study compares two techniques for helping two patients with phonological alexia regain the ability to read functors and verbs. One technique follows the approach of reorganization of function, while the other relies on the stimulation approach. Study 1, employing a reorganization approach, resulted in both patients increasing their reading accuracy from approximately 10 to 90% or greater. Study 2, using a stimulation approach, resulted in significant improvement, however neither patient was able to achieve accuracy greater than 59%. Study 3 reverted back to the reorganization approach using the same words from Study 2. Both patients demonstrated significant success, achieving 90% or greater accuracy. Whereas the reorganization approach meets with far greater success than the stimulation approach, both approaches can be seen as instances of paired associate learning. An explanation of the advantage of the reorganization approach is developed which focuses on the nature of the pairings in the paired associate learning paradigm: it is proposed that pairings within the same level of representation are easier to learn than pairings that cut across levels of representation.


Assuntos
Dislexia/terapia , Leitura , Semântica , Idoso , Dislexia/fisiopatologia , Dislexia/reabilitação , Feminino , Humanos , Masculino , Processos Mentais , Pessoa de Meia-Idade , Análise e Desempenho de Tarefas
5.
Neuron ; 30(2): 609-17, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11395018

RESUMO

The hypothesis that ventral/anterior left inferior frontal gyrus (LIFG) subserves semantic processing and dorsal/posterior LIFG subserves phonological processing was tested by determining the pattern of functional connectivity of these regions with regions in left occipital and temporal cortex during the processing of words and word-like stimuli. In accordance with the hypothesis, we found strong functional connectivity between activity in ventral LIFG and activity in occipital and temporal cortex only for words, and strong functional connectivity between activity in dorsal LIFG and activity in occipital and temporal cortex for words, pseudowords, and letter strings, but not for false font strings. These results demonstrate a task-dependent functional fractionation of the LIFG in terms of its functional links with posterior brain areas.


Assuntos
Mapeamento Encefálico , Lobo Frontal/fisiologia , Idioma , Lobo Occipital/fisiologia , Lobo Temporal/fisiologia , Adulto , Encéfalo/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neurônios/fisiologia , Leitura
6.
Brain Lang ; 72(3): 219-37, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10764518

RESUMO

Following the notion that patients with pure alexia have access to two distinct reading strategies-letter-by-letter reading and semantic reading-a training program was devised to facilitate reading via semantics in a patient with pure alexia. Training utilized brief stimulus presentations and required category judgments rather than explicit word identification. The training was successful for trained words, but generalized poorly to untrained words. Additional studies involving oral reading of nouns and of functors also resulted in improved reading of trained words. Pseudowords could not be trained to criterion. The results suggest that improved reading can be achieved in pure alexia by pairing rapidly presented words with feedback. Focusing on semantic processing is not essential to this process. It is proposed that the training strengthens connections between the output of visual processing and preexisting orthographic representations.


Assuntos
Dislexia/diagnóstico , Dislexia/terapia , Semântica , Vocabulário , Humanos , Masculino , Pessoa de Meia-Idade
7.
J Cogn Neurosci ; 12(2): 281-97, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10771412

RESUMO

Brain activation studies of orthographic stimuli typically start with the premise that different types of orthographic strings (e.g., words, pseudowords) differ from each other in discrete ways, which should be reflected in separate and distinct areas of brain activation. The present study starts from a different premise: Words, pseudowords, letterstrings, and false fonts vary systematically across a continuous dimension of familiarity to English readers. Using a one-back matching task to force encoding of the stimuli, the four types of stimuli were visually presented to healthy adult subjects while fMRI activations were obtained. Data analysis focused on parametric comparisons of fMRI activation sites. We did not find any region that was exclusively activated for real words. Rather, differences among these string types were mainly expressed as graded changes in the balance of activations among the regions. Our results suggest that there is a widespread network of brain regions that form a common network for the processing of all orthographic string types.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Leitura , Vias Visuais/fisiologia , Redação , Adulto , Feminino , Humanos , Idioma , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Lobo Parietal/fisiologia , Lobo Temporal/fisiologia
9.
Neuropsychology ; 13(3): 350-8, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10447297

RESUMO

Patients with probable Alzheimer's disease (AD) are reported to show mild, but reliable, difficulties reading aloud and spelling to dictation exception words, which have unusual or unpredictable correspondence between their spelling and pronunciation (e.g., touch). To understand the cognitive dysfunction responsible for these impairments, 21 patients and 27 age-and education-matched controls completed specially designed tests of single-word oral reading and spelling to dictation. AD patients performed slightly below controls on all tasks and showed mildly exaggerated regularity effects (i.e., the difference in response accuracy between words with regular spellings minus exception words) in reading and spelling. Qualitative analyses, however, did not demonstrate response patterns consistent with impairment in central lexical orthographic processing. The authors conclude that the mild alexia and agraphia in AD reflect semantic deficits and nonlinguistic impairments rather than a specific disturbance in lexical orthographic processing.


Assuntos
Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico , Leitura , Distúrbios da Fala/etiologia , Comportamento Verbal , Idoso , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Probabilidade , Índice de Gravidade de Doença
10.
Neuropsychologia ; 37(7): 807-15, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10408648

RESUMO

Different kinds of real words and pronounceable pseudowords (PWs) were presented for writing to dictation to patients with the diagnosis of probable Alzheimer's disease (AD) and to age- and education-matched healthy controls. Though spelling less accurately on all tasks, AD patients responded in a manner generally qualitatively similar to controls. Except for a slightly enhanced effect of spelling regularity in real word writing accuracy, AD patients showed the same sensitivity to various lexical, orthographic and phonological variables as controls. Both groups showed no difference in spelling accuracy for words and PWs with regular vs ambiguous spelling patterns, and groups also showed similar orthographic preferences when spelling PWs having several different acceptable pronunciations. Finally, AD patients and controls produced similar types of errors when spelling real words. Dementia severity was related to the overall accuracy, but not to the pattern, of spelling responses. It is suggested that the decline in response accuracy in cognitively demanding writing tasks in patients with more advanced dementia is most likely due to semantic impairment and impairments of nonlinguistic functions of attention, executive control and praxis, rather than to a disturbance within language specific processes.


Assuntos
Agrafia/fisiopatologia , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/psicologia , Idoso , Envelhecimento , Doença de Alzheimer/complicações , Atenção , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Transtornos Cognitivos/etiologia , Escolaridade , Feminino , Humanos , Linguística , Masculino , Análise por Pareamento , Índice de Gravidade de Doença , Testes de Associação de Palavras
11.
Brain Lang ; 67(3): 188-201, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10210630

RESUMO

An experimental treatment study designed to improve both the accuracy and the speed of reading was administered to a patient with pure alexia and impaired letter naming. The study focused on the use of letter-by-letter reading. A two-stage approach was employed. The first stage implemented a tactile-kinesthetic strategy to improve accuracy. The second stage concentrated on speed. At the end of the treatment, patient DL was reading both trained and untrained words more accurately and with considerably greater speed than prior to treatment. Accuracy and speed of reading at the sentence level improved as well.


Assuntos
Dislexia Adquirida/terapia , Linguística , Leitura , Idoso , Dislexia Adquirida/diagnóstico , Humanos , Cinestesia , Masculino , Índice de Gravidade de Doença , Tato/fisiologia , Resultado do Tratamento
12.
Int J Radiat Oncol Biol Phys ; 44(2): 289-96, 1999 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10760421

RESUMO

PURPOSE: Chemotherapy and accelerated superfractionated radiotherapy were prospectively applied for inflammatory breast carcinoma with the intent of breast conservation. The efficacy, failure patterns, and patient tolerance utilizing this approach were analyzed. METHODS AND MATERIALS: Between 1983 and 1996, 52 patients with inflammatory breast carcinoma presented to the Medical College of Virginia Hospitals of VCU and the New England Medical Center. Thirty-eight of these patients were jointly evaluated in multidisciplinary breast clinics and managed according to a defined prospectively applied treatment policy. Patients received induction chemotherapy, accelerated superfractionated radiotherapy, selected use of mastectomy, and concluded with additional chemotherapy. The majority were treated with 1.5 Gy twice daily to field arrangements covering the entire breast and regional lymphatics. An additional 18-21 Gy was then delivered to the breast and clinically involved nodal regions. Total dose to clinically involved areas was 63-66 Gy. Following chemoradiotherapy, patients were evaluated with physical examination, mammogram, and fine needle aspiration x 3. Mastectomy was reserved for those patients with evidence of persistent or progressive disease in the involved breast. All patients received additional chemotherapy. RESULTS: Median age was 51 years. Median follow-up was 23.9 months (6-86) months. The breast preservation rate at the time of last follow-up was 74%. The treated breast or chest wall as the first site of failure occurred in only 13%, and the ultimate local control rate with the selected use of mastectomy was 74%. Ten patients underwent mastectomy, 2 of which had pathologically negative specimens despite a clinically palpable residual mass. Response to chemotherapy was predictive of treatment outcome. Of the 15 patients achieving a complete response, 87% remain locoregionally controlled without the use of mastectomy. Five-year overall survival for complete responders was 68%. This is in contrast to the 14% 5-year overall survival observed with incomplete responders. The 5-year actuarial disease-free survival and overall survival for the entire patient cohort was 11% and 33%, respectively. All patients tolerated irradiation with limited acute effects, of which all were managed conservatively. CONCLUSION: Our experience demonstrates that induction chemotherapy, accelerated superfractionated radiotherapy, and the selected use of mastectomy results in excellent locoregional control rates, is well tolerated, and optimizes breast preservation. Based on our present results, we recommend that a patient's response to induction chemotherapy guide the treatment approach used for locoregional disease, such that mastectomy be reserved for incomplete responders and avoided in those achieving a complete response.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/radioterapia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Ductal de Mama/radioterapia , Adenocarcinoma/cirurgia , Adulto , Idoso , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Terapia Combinada , Ciclofosfamida/administração & dosagem , Árvores de Decisões , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Doxorrubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Mastectomia , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Estudos Prospectivos , Indução de Remissão , Falha de Tratamento
13.
Brain Lang ; 63(1): 32-49, 1998 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9642019

RESUMO

Repetition and reading of various types of pronounceable nonwords (pseudowords) was examined in patients with probable Alzheimer's disease (AD) and healthy elderly controls. Overall accuracy of performance was lower in AD patients compared to controls, but the two groups showed qualitatively similar response patterns when reading different kinds of pseudowords aloud and when repeating pseudowords composed of familiar phonological forms, analogous to those in real English words. AD patients diverged in performance from controls, however, when repeating pseudowords composed of phonologically unusual forms. These results support two conclusions: (1) Aspects of phonological processing may become disrupted in AD patients in association with increasing dementia severity, while orthographic processing remains comparatively less impaired. (2) The results are consistent with the view that the processing of pseudowords is achieved through the same system as real words, and further show that the influence of prior language experience on the processing of novel linguistic forms occurs primarily at the level of phonological, rather than orthographic processing.


Assuntos
Doença de Alzheimer/psicologia , Transtornos da Linguagem/psicologia , Idoso , Doença de Alzheimer/complicações , Análise de Variância , Dislexia Adquirida/etiologia , Dislexia Adquirida/psicologia , Humanos , Transtornos da Linguagem/etiologia , Fonética , Psicolinguística , Estados Unidos
14.
Neuropsychology ; 12(2): 218-24, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9556768

RESUMO

Semantic memory impairment was investigated in patients with probable Alzheimer's disease (AD) using a threshold oral word reading task to assess priming of different lexical relationships. Healthy elderly controls showed significant priming for associatively related nouns (tempest-teapot) and also for nouns semantically related either because both designate basic-level exemplars of a common superordinate category (cousin-nephew) or because the target names the superordinate category of the prime (daughter-relative). AD patients, in contrast, showed preserved priming of lexical associates but impaired priming of certain semantic relationships. They showed no priming between words designating coordinate exemplars within a category, despite preserved priming of the superordinate category label. Findings are consistent with the view that at least part of the semantic deficit in AD is due to disruption of semantic knowledge that affects relationships among basic-level concepts, more than the relationships between these concepts and their corresponding superordinate category of membership.


Assuntos
Doença de Alzheimer/fisiopatologia , Associação , Sinais (Psicologia) , Leitura , Semântica , Vocabulário , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Formação de Conceito/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Brain Lang ; 56(2): 234-47, 1997 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9027372

RESUMO

Recent evidence from patients with progressive language disorders and dementia has been used to suggest that phonological and orthographic processing depend on intact semantic memory. These claims challenge the traditional view that there are functionally separate modules in the language system. The effect of a severe, but nonprogressive, semantic impairment on phonological and orthographic processing was evaluated in LA, a mentally retarded child with hyperlexia. Knowledge of a word's meaning did not affect LA's word repetition, a measure of phonological processing, or his acquisition and retention of orthographic patterns for writing to dictation low-frequency words with exceptional spellings. These findings support the assertion that both orthographic and phonological whole-word representations can be acquired, stored, and retrieved in the absence of a functional link to semantic memory.


Assuntos
Transtornos da Linguagem/complicações , Transtornos da Memória/complicações , Transtornos da Memória/diagnóstico , Fonética , Semântica , Criança , Humanos , Masculino , Leitura , Aprendizagem Verbal
17.
Cortex ; 33(4): 653-66, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9444467

RESUMO

Repetition of single words and pronounceable nonwords (pseudowords) was assessed in Alzheimer's Disease (AD) patients to evaluate how lexical phonological processing might be accomplished when semantic and conceptual knowledge is impaired. AD patients performed significantly worse than healthy elderly controls on all repetition tasks. However, repetition abilities and dementia severity were not correlated, and AD patients produced the same distribution of error types as controls. Furthermore, despite their semantic problems, AD patients, like controls, showed a significant advantage for repeating real words compared to pseudowords, even when repeating low frequency phonologically complex words whose meaning is not likely to have been retained. The results support the postulated existence of a lexical phonological system that is used to repeat both known and novel words and that processes linguistic information independent of its meaning.


Assuntos
Doença de Alzheimer/psicologia , Memória/fisiologia , Aprendizagem Verbal/fisiologia , Idoso , Humanos , Processos Mentais/fisiologia , Testes Neuropsicológicos , Semântica
18.
Acad Med ; 71(9): 979-81, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9125986

RESUMO

The Internet's World Wide Web (WWW) offers educators a unique opportunity to introduce computer-assisted instructional (CAI) programs into the medical school curriculum. With the WWW, CAI programs developed at one medical school could be successfully used at other institutions without concern about hardware or software compatibility; further, programs could be maintained and regularly updated at a single central location, could be distributed rapidly, would be technology-independent, and would be presented in the same format on all computers. However, while the WWW holds promise for CAI, the author discusses ten reasons that educators' efforts to fulfill the Web's promise may fail, including the following: CAI is generally not fully integrated into the medical school curriculum; students are not tested on material taught using CAI; and CAI programs tend to be poorly designed. The author argues that medical educators must overcome these obstacles if they are to make truly effective use of the WWW in the classroom.


Assuntos
Redes de Comunicação de Computadores , Instrução por Computador/normas , Educação Médica/métodos , Humanos , Estados Unidos
19.
Brain Lang ; 52(1): 114-28, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8741978

RESUMO

Reports of five patients whose deep alexic reading all evolved into phonological alexia in a similar fashion point to the hypothesis that deep alexia and phonological alexia represent different points on the same continuum. This hypothesis is explored further through an examination of previously published case reports of eleven patients with phonological alexia. Data from these patients suggest that there is a predictable succession of symptoms which form a continuum of severity of phonological alexia, with deep alexia as its endpoint. An account of the recovery from deep to phonological alexia, based upon a lexical (no-rules) model of reading, is provided (Glosser & Friedman, 1990), and the implications for therapy are considered. The significance of the notion of a continuum of phonological/deep alexia is discussed.


Assuntos
Encéfalo/fisiopatologia , Convalescença , Dislexia Adquirida/fisiopatologia , Adolescente , Adulto , Dislexia Adquirida/diagnóstico , Feminino , Lateralidade Funcional , Humanos , Masculino , Semântica
20.
Cortex ; 31(2): 397-403, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7555016

RESUMO

It is hypothesized, on the basis of a lexical model of reading, that there are two different underlying causes of phonological alexia. It is predicted that these two types of phonological alexia will be accompanied by different sets of symptoms. Published cases of phonological alexia are examined for evidence in support of these predictions. Two distinct groups of phonological alexic patients are observed. These results support the notion of two types of phonological alexia. The failure to find any phonological alexic patients who do not fall into one of these two categories provides evidence against non-lexical reading models.


Assuntos
Dislexia Adquirida/diagnóstico , Leitura , Dislexia Adquirida/classificação , Humanos , Idioma , Modelos Psicológicos , Análise e Desempenho de Tarefas
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