RESUMO
The Japanese language is represented by two different codes: syllabic and logographic while Portuguese employs an alphabetic writing system. Studies on bilingual Portuguese-Japanese individuals with acquired dyslexia therefore allow an investigation of the interaction between reading strategies and characteristics of three different writing codes. The aim of this study was to examine the differential impact of an acquired brain lesion on the reading of the logographic, syllabic and alphabetic writing systems of a bilingual Portuguese-Japanese aphasic patient (PF). Results showed impaired reading in the logographic system and when reading irregularly spelled Portuguese words but no effects on reading regular words and nonwords in syllabic and alphabetic writing systems. These dissociations are interpreted according to a multi-route cognitive model of reading assuming selective damage in the lexical route can result in acquired dyslexia across at least three different writing codes.
Assuntos
Afasia/fisiopatologia , Dislexia Adquirida/fisiopatologia , Multilinguismo , Psicolinguística , Leitura , Encéfalo/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , RedaçãoRESUMO
Twenty-one patients with right hemisphere damage were studied (11 men, 10 women; average age = 41.33; range = 19-65). Patients were divided in two groups: pre-Rolandic (six patients) and retro-Rolandic (15 patients) right hemisphere damage. A special reading test was given to each patient. The observed errors included: literal errors (substitutions, additions, and omissions of letters), substitutions of syllables and pseudowords for meaningful words, left hemispatial neglect, confabulation, splitting of words, verbal errors (substitutions, additions, and omission of words), grouping of letters belonging to two different words, misuse of punctuation marks, and errors in following lines. It was proposed that spatial alexia is characterized by: (1) some difficulties in the recognition of the spatial orientation in letters; (2) left hemispatial neglect; (3) tendency to "complete" the sense of words and sentences; (4) inability to follow lines when reading texts, and sequentially explore the spatial distribution of the written material; and (5) grouping and fragmentation of words, most likely as a consequence of the inability to interpret the relative value of spaces between letters correctly.
Assuntos
Encefalopatias/diagnóstico , Dislexia Adquirida/diagnóstico , Lateralidade Funcional/fisiologia , Percepção Espacial , Adulto , Idoso , Atenção , Encefalopatias/complicações , Encefalopatias/fisiopatologia , Colômbia/etnologia , Dislexia Adquirida/etiologia , Dislexia Adquirida/fisiopatologia , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Transtornos da Percepção/etiologia , Transtornos da Percepção/fisiopatologia , EspanhaRESUMO
Although many patients with dominant hemisphere damage retain some reading ability, the anatomic substrate of the preserved reading remains controversial. We tested the hypothesis that the right hemisphere mediates the reading of some patients with acquired dyslexia by using Transcranial Magnetic Stimulation (TMS) to assess the effect of transient cortical stimulation on reading. A patient with (partially recovered) pure alexia was asked to read aloud briefly presented words, half of which were shown in association with TMS of the right or left hemisphere. Consistent with the right hemisphere reading hypothesis, stimulation of the right but not the left hemisphere disrupted oral reading.
Assuntos
Corpo Caloso/fisiologia , Lateralidade Funcional/fisiologia , Corpos Geniculados/fisiologia , Leitura , Estimulação Magnética Transcraniana , Infarto Cerebral/patologia , Infarto Cerebral/fisiopatologia , Corpo Caloso/patologia , Corpo Caloso/fisiopatologia , Dislexia Adquirida/patologia , Dislexia Adquirida/fisiopatologia , Corpos Geniculados/patologia , Corpos Geniculados/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-IdadeRESUMO
A number of investigators have demonstrated that patients with pure alexia comprehend briefly presented words which they are unable to explicitly identify. We suggested previously that these patients may read by means of two distinct procedures: a laborious letter-by-letter method and a 'whole-word' procedure which, at least initially, does not support explicit word identification. We report a test of this proposal in a patient with pure alexia. We reasoned that if the patient had access to two distinct and incompatible procedures, he might be induced to switch from one to the other by changing task demands. We found that when instructed to name words, the patient employed a letter-by-letter strategy; in contrast, when instructed to make lexical decision or semantic judgements about rapidly presented words, he appeared to use a 'whole-word' strategy. These data support the hypothesis that two distinct procedures are available to this patient. We argue, further, that is necessary to suppress use of the letter-by-letter strategy to demonstrate whole word reading capability in pure alexics, and that failure to do so may account for negative findings in other cases reported in the literature.
Assuntos
Dislexia Adquirida/fisiopatologia , Leitura , Infarto Cerebral/complicações , Humanos , Testes de Linguagem , Masculino , Pessoa de Meia-Idade , SemânticaRESUMO
Se presenta el caso de un paciente afásico quien muestra una producción inusitada de paralexias semánticas durante la lectura en voz alta de palabras y frases. No hemos encontrado en la literatura ninguna publicación que haga referencia a la producción de este síntoma en pacientes hispanoparlantes. Por el contrario, dada la transparencia del sistema lectográfico español (alta correspondencia grafema/fonema) se ha puesto en duda que las parilexias semánticas y el síndrome aléxico correspondiente (dislexia profunda) puedan presentarse en hispanoparlantes. Nuestro caso desdice esta presunción y permite discutir aspectos relevantes de los modelos neuropsicológicos de la lectura
Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Afasia de Broca/etiologia , Transtornos Cerebrovasculares , Disartria/diagnóstico , Dislexia Adquirida/diagnóstico , Afasia/etiologia , Afasia de Broca/diagnóstico , Afasia de Broca/fisiopatologia , Apraxias/etiologia , Aneurisma Intracraniano/complicações , Disartria/diagnóstico , Dislexia Adquirida/etiologia , Dislexia Adquirida/fisiopatologia , Transtornos da Linguagem/diagnóstico , Transtornos da Linguagem/etiologia , Testes de Linguagem/instrumentaçãoRESUMO
Se presenta el caso de un paciente afásico quien muestra una producción inusitada de paralexias semánticas durante la lectura en voz alta de palabras y frases. No hemos encontrado en la literatura ninguna publicación que haga referencia a la producción de este síntoma en pacientes hispanoparlantes. Por el contrario, dada la transparencia del sistema lectográfico español (alta correspondencia grafema/fonema) se ha puesto en duda que las parilexias semánticas y el síndrome aléxico correspondiente (dislexia profunda) puedan presentarse en hispanoparlantes. Nuestro caso desdice esta presunción y permite discutir aspectos relevantes de los modelos neuropsicológicos de la lectura
Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Dislexia Adquirida/diagnóstico , Disartria/diagnóstico , Transtornos Cerebrovasculares , Afasia de Broca/etiologia , Afasia/etiologia , Afasia de Broca/diagnóstico , Afasia de Broca/fisiopatologia , Aneurisma Intracraniano/complicações , Dislexia Adquirida/etiologia , Dislexia Adquirida/fisiopatologia , Disartria/diagnóstico , Apraxias/etiologia , Transtornos da Linguagem/diagnóstico , Transtornos da Linguagem/etiologia , Testes de Linguagem/instrumentaçãoRESUMO
The authors report the clinical findings and CT-scanning results in two cases of alexia without agraphia and review the literature on this subject. Both patients had extensive infarction in the territory supplied by the left posterior cerebral artery and developed severe alexia without agraphia, right hemianopia without color-anomia and one of them presented with transient verbal memory difficulties. In both cases the evolution was very good, with total regression of the alexia after 17 months in the first patient and almost complete recovery after there months in the second one. The authors comment on the causes and possible mechanisms of the alexias, especially of the alexia without agraphia, and suggest that every patient with right hemianopic disturbances due to occlusion of the left posterior cerebral artery be thoroughly studied from a neurological point of view, so that this syndrome can be detected since, notwithstanding its recognized rarity, it seems highly probable that many cases have been overlooked as a result of incomplete examination of the patients.
Assuntos
Dislexia Adquirida/diagnóstico , Tomografia Computadorizada por Raios X , Adulto , Agrafia/fisiopatologia , Infarto Cerebral/complicações , Dislexia Adquirida/etiologia , Dislexia Adquirida/fisiopatologia , Feminino , Humanos , MasculinoRESUMO
The author studies the written language in a series of right-handed patients with a right side cerebral lesion. Reduplications and omission of strokes and of letters are noted on writing. The cause of these disorders is attributed by the author to an impairment of visual and kinesthetic control of the act of writing, and not to a truly aphasic alteration. This impairment is part of a more general deficit, namely a distorted interpretation of spatial data. The author proposes to call this writing disorder afferent dysgraphia.