11/79. writing with the right hemisphere.We studied writing abilities in a strongly right-handed man following a massive stroke that resulted in virtually complete destruction of the language-dominant left hemisphere. writing was characterized by sensitivity to lexical-semantic variables (i.e., word frequency, imageability, and part of speech), semantic errors in writing to dictation and written naming, total inability to use the nonlexical phonological spelling route, and agrammatism in spontaneous writing. The reliance on a lexical-semantic strategy in spelling, semantic errors, and impaired phonology and syntax were all highly consistent with the general characteristics of right hemisphere language, as revealed by studies of split-brain patients and adults with dominant hemispherectomy. In addition, this pattern of writing closely resembled the syndrome of deep agraphia. These observations provide strong support for the hypothesis that deep agraphia reflects right hemisphere writing.- - - - - - - - - - ranking = 1keywords = agraphia (Clic here for more details about this article) |
12/79. Posterior cortical dementia with alexia: neurobehavioural, MRI, and PET findings.A progressive disorder of relatively focal but asymmetric biposterior dysfunction is described in a 54 year old right handed male. Initial clinical features included letter-by-letter alexia, visual anomia, acalculia, mild agraphia, constructional apraxia, and visuospatial compromise. Serial testing demonstrated relentless deterioration with additional development of transcortical sensory aphasia, Gerstmann's tetrad, and severe visuoperceptual impairment. amnesia was not an early clinical feature. judgment, personality, insight, and awareness remained preserved throughout most of the clinical course. Extinction in the right visual field to bilateral stimulation was the sole neurological abnormality. Early CT was normal and late MRI showed asymmetrical bioccipitoparietal atrophy with greater involvement of the left hemisphere. Results from positron emission tomography (PET) showed bilaterally asymmetric (left greater than right) occipitotemporoparietal hypometabolism. The metabolic decrement was strikingly asymmetric with a 50% reduction in glucose consumption confined to the left occipital cortex. The picture of occipitotemporoparietal compromise verified by MRI, PET, and neurobehavioural testing would be unusual for such degenerative dementias as Alzheimer's (AD) and Pick's disease, although atypical AD with predominant occipital lobe involvement cannot be excluded. This case supports the concepts of posterior cortical dementia (PCD) as a clinically distinct entity and for the first time documents its corresponding metabolic deficit using PET.- - - - - - - - - - ranking = 0.5keywords = agraphia (Clic here for more details about this article) |
13/79. Alexia without agraphia, hemianopia, or color-naming defect: a disconnection syndrome.A patient with alexia without agraphia, hemianopia, or color-naming defect was found at operation to have a meningioma arising from the tentorium cerebelli that compressed the inferior aspect of the left temporal-occipital junction. It is presumed to have involved only the left ventral visual association cortex and its inferior outflow tracts to the angular gyrus. The input from the right occipital area also was disconnected from the visual language verbal association area by involvement of the ventral outflow of the splenium of the corpus callosum. Preservation of color naming and matching suggests that these functions are dependent on the integrity of more dorsal occipital association systems.- - - - - - - - - - ranking = 2.5keywords = agraphia (Clic here for more details about this article) |
14/79. Alexia without agraphia associated with spleniogeniculate infarction.Pure alexia, following an infarction in the distribution of the left posterior cerebral artery, is attributed to damage of the left occipital lobe and the splenium of the corpus callosum. We describe a case of pure alexia in a 57-year-old woman with infarction of the left lateral geniculate body and the splenium of the corpus callosum, a variation on this classic disconnection syndrome.- - - - - - - - - - ranking = 2keywords = agraphia (Clic here for more details about this article) |
15/79. Intermittent alexia.A case of intermittent alexia, sometimes accompanied by severe dysgraphia and sometimes by mild dysgraphia, which had a probable migrainous origin, is described. On some occasions the patient could write to dictation, although with many errors, while unable to read words or letters. On other occasions the patient's writing to dictation was seriously disordered in terms of content and the letters were produced clumsily. reading of numbers, colour vision and colour naming were normal although impairments on right-left orientation and visual short term memory were present and a mild finger agnosia was apparent. blood flow scans (SPECT) taken under normal and alexic conditions support the view that the disturbance had a vascular origin.- - - - - - - - - - ranking = 0.025536120817406keywords = dysgraphia (Clic here for more details about this article) |
16/79. Troubled letters but not numbers. Domain specific cognitive impairments following focal damage in frontal cortex.A well educated right-handed woman developed severe and stable alexia and agraphia following a circumscribed surgical lesion in the left premotor cortex. The lesion was located in Brodmann's field 6, above Broca's area, in the region traditionally referred to as Exner's area. The alexia and agraphia occurred in a pure form, that is, in the setting of otherwise normal cognitive and neurological function. She was not aphasic or hemiparetic and her visual perception, intellect, memory, oral spelling and drawing were normal. The patterns of impairment of reading and writing closely paralleled one another. reading of single words and letters was severely impaired, and she was entirely unable to read sentences. She was virtually unable to write recognizable letters, could write no words, and her writing attempts were severely distorted spatially. By contrast, she could easily read all numbers and nonverbal symbols, and she was equally able to write numbers and perform written calculations without difficulty. These striking dissociations provide further evidence of the domain specificity of cognitive/neural representations. They also point to the possible role of premotor cortices in the coactivation of precise sequences of motor and sensory activity patterns involved in reading and writing.- - - - - - - - - - ranking = 1keywords = agraphia (Clic here for more details about this article) |
17/79. The graphemic buffer and attentional mechanisms.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.- - - - - - - - - - ranking = 0.012768060408703keywords = dysgraphia (Clic here for more details about this article) |
18/79. Recognizing orally spelled words: an analysis of procedures shared with reading and spelling.Some investigators have suggested that recognizing orally spelled words is dependent on the same procedures ordinarily used in spelling, whereas others have viewed it either as dependent on reading procedures or as an independent ability. In the present study, a single subject with dyslexia and dysgraphia was examined on parallel tests of recognizing orally spelled words, reading, and spelling (writing), and a comparison was made of his performance on the three tasks. On both words and nonwords, the patient's errors in recognizing orally spelled words and in reading were alike, whereas his spelling errors were often different. The distinction between recognizing orally spelled words and spelling was further shown by his inability to recognize a set of orally spelled words that he could write correctly to dictation or on the basis of word meaning. These findings suggest that the procedures normally used for reading can accept sequences of letter identities as input when orally spelled words must be recognized.- - - - - - - - - - ranking = 0.012768060408703keywords = dysgraphia (Clic here for more details about this article) |
19/79. Lexical agraphia in the Japanese language. Pure agraphia for Kanji due to left posteroinferior temporal lesions.A new syndrome of 'pure agraphia for Kanji' is described in 3 Japanese subjects with lesions in the left posteroinferior temporal region. Kanji (ideogram or morphogram) can be compared with orthographically irregular or ambiguous words in some European languages, since it is impossible to write Kanji characters unless each one of them is learned and memorized. In contrast, Kana (phonogram or syllabogram) words are comparable with orthographically regular words or nonsense words, because the Kana writing system depends on strict phonological rules (almost one-to-one correspondence between syllable and syllabogram). We conclude that 'lexical agraphia' reported in European languages can also be observed in the Japanese language where it is expressed as 'pure agraphia for Kanji'. 'Lexical agraphia' is a useful concept with general application regardless of language system.- - - - - - - - - - ranking = 6keywords = agraphia (Clic here for more details about this article) |
20/79. Alexia with agraphia.The authors presented a case of relatively pure syndrome of alexia with agraphia in a patient speaking Serbo-Croatian language. reading disturbances showed some characteristics of a deep dyslexia. Besides severely impaired reading and writing abilities, some components of Gerstamnn's syndrome were also present. infarction in the posterior half of the left supramarginal and in the anterior half of the left angular gyrus was accurately located by the graphic reconstruction of CT scans.- - - - - - - - - - ranking = 2.5keywords = agraphia (Clic here for more details about this article) |
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