1/35. Metabolic abnormalities detected by 1H-MRS in dyscalculia and dysgraphia.Proton MRS was performed in a patient with developmental acalculia. The results indicated a focal, wedge-shaped defect in the left temporoparietal brain region near the angular gyrus, with differential decreases in N-acetyl-aspartate, creatine, and choline. These results support the hypothesis that developmental acalculia, like acquired acalculia, is associated with left posterior hemisphere lesions.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
2/35. Developmental Gerstmann's syndrome: a distinct clinical entity of learning disabilities.The symptom complex of finger anomia, right-left disorientation, dysgraphia, and dyscalculia constitutes Gerstmann's syndrome. It is mostly described in adults and is caused by acquired lesions of the dominant parietal lobe. It is infrequently described in children with learning disabilities and has been designated developmental Gerstmann's syndrome. Developmental Gerstmann's syndrome goes unnoticed if not specifically sought by clinicians. A detailed evaluation will reveal subtle neurologic deficits, behavioral problems, and neuropsychologic and specific speech and language abnormalities. Ten such patients are reported; six of the children demonstrated improvement with intensive speech training. Early identification and intervention is therefore crucial, and even more important in cultures in which students are required to be biliterate or triliterate, further increasing the constraints on writing. A selective writing, reading, or calculation abnormality in the presence of normal oral communication triggers several interesting possibilities for the brain mechanisms behind normal language processing. Similarly, the association of acalculia with finger anomia and agraphia with right-left disorientation may have specific implications in the neuropsychologic processing of the evolution of calculation and writing. A theoretical possibility of oral and written language processing from the observation of the language behavior of these children is also described.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
3/35. Superior written over spoken picture naming in a case of frontotemporal dementia.Two main hypotheses have been proposed regarding the role of phonology in written word production. According to the phonological mediation hypothesis, the retrieval of the lexical phonological representation of a word is an obligatory prerequisite to the retrieval of its spelling. Therefore, deficits to the phonological lexicon should affect both spoken and written picture naming. In contrast, the orthographic autonomy hypothesis posits that the lexical orthographic representations of words can be accessed without any necessary phonological mediation. In support of this view, cases of preserved written naming despite impaired lexical phonology have been reported following brain damage. In this report, we replicate this basic pattern of performance in case YP, a 60-year-old woman with a pattern of frontotemporal dementia. As her disease progressed, YP's ability to write down the names of pictures remained very good despite a severe decline in oral naming. Further testing indicated that this deficit was not primarily due to an articulatory or post-lexical phonological deficit. YP's case provides strong additional support for the orthographic autonomy hypothesis. The significance of this case with respect to the characterization of dementia syndromes is discussed.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
4/35. Alexia without agraphia: a century later.A case of alexia without agraphia is presented. It is a rare but classic disconnection syndrome, first described by Dejerine in 1892. Recent advances in modern neuroimaging techniques such as FLAIR MRI can now localise in vivo the site of origin of the syndrome, especially when computerised axial tomogram of the brain is normal.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
5/35. gerstmann syndrome in systemic lupus erythematosus: neuropsychological, neuroimaging and spectroscopic findings.gerstmann syndrome (GS) comprises four interlaced neuropsychological symptoms including finger agnosia, right-left confusion, agraphia, and acalculia. While GS is commonly associated with focal lesions to the region of the left angular gyrus, it has also been associated with numerous diffuse etiologies including atrophy, alcoholism, carbon monoxide poisoning, lead intoxication and anaphylactic shock. Thus, a vigorous debate has emerged as to whether GS represents a syndrome arising from general brain decline or a distinct and localizing lesion. We report a right-handed patient who developed neuropsychological dysfunction secondary to systemic lupus erythematosus (SLE). Neuropsychological evaluation found the patient to exhibit symptoms consistent with the GS tetrad, as well as general cognitive decline. magnetic resonance imaging revealed a distinct focal lesion of the left parieto-occipital white matter underlying the angular gyrus as well as diffuse atrophy. (1)H-magnetic resonance spectroscopy revealed substantial metabolic derangement in a voxel placed within the visible lesion, although substantial metabolic derangement was observed in regions remote from the focal pathology. Thus, GS in this first case in SLE would appear to comprise a focal neurological tetrad of disorders within a more general pattern of cognitive decline and metabolic derangement.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
6/35. The organization of letter-form representations in written spelling: evidence from acquired dysgraphia.We report on an Italian brain-damaged patient with impaired written spelling. The patient's errors, in different fonts and scripts, consist mainly of letter substitutions (e.g., filo [thread] --> TILO). The results of various tests indicate that letter substitution errors arise because of a deficit in accessing the letter-form representations supporting written spelling. letter substitutions occurred predominantly between letters with common strokes (e.g., C and G; b and p). Similarities in terms of global letter shape or letter sound were not valid predictors of letter substitution errors. letter frequency, consonant-vowel status, and letter gemination were factors affecting letter substitution errors. The results of our investigation suggest that information about letter strokes are stored at the level of letter-form representations, and that access to these representations is sensitive to letter frequency. The results further indicate that letter-form representations do not specify whether a letter is a consonant or a vowel, or is a geminate.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
7/35. Phonological agraphia after superior temporal gyrus infarction.BACKGROUND: Phonological agraphia refers to a condition in which the ability to write nonwords to dictation is impaired, while writing words to dictation is preserved, as is oral repetition of the words and nonwords. This condition has been regarded as reflecting a disconnection within the phonological writing system, and previous neurolinguistic correlations suggested that the anterior-inferior supramarginal gyrus was a crucial link within the system. SETTING: A neurology department of a university hospital. PATIENT: A 51-year-old right-handed man presented with speech disturbances. On initial evaluation of his language, his deficit was consistent with that of conduction aphasia, which improved rapidly to an apparently normal level. A subsequent detailed examination of oral and written repetition of words and nonwords revealed a rather selective form of phonological agraphia. A magnetic resonance imaging scan of his brain showed a focal ischemic lesion at the left posterior superior temporal gyrus and at the underlying white matter. CONCLUSIONS: In contrast to most previously described patients, this patient showed a selective impairment of phonological agraphia in association with a focal infarction restricted to the left posterior superior temporal gyrus, suggesting that this region of the brain is an important node within a wider network of areas that subserve the phonological route for writing.- - - - - - - - - - ranking = 2keywords = brain (Clic here for more details about this article) |
8/35. Crossed aphasia with left spatial neglect and visual imperception: a case report.A 64-year-old right-handed woman with no left-handers in the family developed aphasia associated with moderate left hemiparesis and dense left homonymous hemianopia following rupture of a right middle cerebral artery aneurysm and subsequent selective surgery confined to the right hemisphere. Severe left spatial neglect and constructional apraxia were also present. The patient was an achondroplasic dwarf whose previous medical and neurological history was otherwise unremarkable. Computed tomography of the brain showed a large right temporo-insulofrontoparietal lesion. language and nonverbal cognitive functions were assessed after 2 and 6 months, and then four years later. A reportedly overall language disruption in the acute period evolved into Wernicke's aphasia and then into a mild form of conduction aphasia. The associated left spatial neglect eventually shrank to a minimum. The patient never had clinically detectable visual agnosia, but on specific tests of visual recognition and perception some impairment was found four years after onset. The left hemiparesis disappeared in time while the left hemianopia persisted. This case is a convincing example of an entirely righthanded person in whom both linguistic and visuospatial functions are represented in the right hemisphere.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
9/35. Surface dysgraphia in a regular orthography: apostrophe use by an Italian writer.The dual-route model of writing assumes two basic procedures involved in writing: lexical and non-lexical. The lexical route is fundamental in opaque orthographies such as English; from its impairment surface dysgraphia arises. Evidence for the role of a lexical route in transparent languages such as Italian, which have a regular orthography, has been more limited. We report a case study of ES, an Italian patient suffering from degenerative brain disease, who presented with a selective disorder of writing. He showed the unusual phenomenon of inserting an apostrophe inappropriately in the spellings of words. Neuropsychological evaluation provided evidence of loss of orthographic meaning of the apostrophe and a pattern of writing performance consistent with surface dysgraphia. There was also evidence of an accompanying surface dyslexia. We conclude that examination of apostrophe use provides a valuable means of detecting surface dysgraphia in the Italian language. The findings point to the need for cognitive models of writing to account for "dumb symbols" of language such as the apostrophe. This unique case provides a further example of the variety of clinical presentations of focal cerebral degeneration.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
10/35. Progressive agraphia, acalculia, and anomia: a single case report.A case of a 50-year-old, right-handed female, mono-lingual native Spanish-speaker with a university-level education and cognitive changes is reported. Over approximately 2 years, she presented with a progressive deterioration of writing abilities associated with acalculia and anomia. An MRI disclosed a left parietal temporal atrophy. Two years later, further significant cognitive decline consistent with a dementia of the Alzheimer's type was observed. amnesia, executive dysfunction, and ideomotor apraxia were found. writing was severely impaired, and some difficulties in reading were observed. Copying abilities, however, were relatively well preserved, and the patient could drive and go to different city locations without significant spatial orientation difficulties. A second MRI approximately 2 years later showed that brain atrophy had progressed significantly. Spontaneous writing and writing to dictation were impossible. The ability to read words was preserved, but the ability to read pseudowords was lost. Changes in calligraphy were noted. This case clearly illustrates the progression of focal cognitive defects over time and the spread of abnormalities to other domains.- - - - - - - - - - ranking = 1keywords = brain (Clic here for more details about this article) |
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