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Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Evidence from recent studies suggests that writing may be an aspect of cognition capable of identifying impairments specific to patients with Alzheimer's Disease (AD). The precise nature and progression of the writing disorder, however, remains unclear. The current study assessed the central and peripheral aspects of writing among a sample of minimal, mild and moderate AD patients and a group of healthy elderly controls on a narrative description task. Comparisons of the two groups indicated that AD patients suffer from a primary impairment at the semantic level. Even those in the minimal stages of the disease could be differentiated from controls on measures of word finding and information conveyed. This semantic impairment was coupled with a secondary milder impairment in phonological processing. The prevalence of phonological errors increased, but no shift in error type (plausible/implausible) was identified as the disease progressed. In addition to the central impairments, patients evinced damage at the peripheral level. In the more severe stages, patients experienced more problems with letter formation and stroke placement and tended to rely upon the more simplistic writing form of print. The writing impairment in AD is multi-componential in nature and follows the pattern of cortical deterioration reported in the brains of AD patients.
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PMID:The evolution of dysgraphia in Alzheimer's disease. 1512 Dec 35

Apraxic agraphia (AA) is a so-called peripheral writing disorder following disruption of the skilled movement plans of writing while the central processes that subserve spelling are intact. It has been observed in a variety of etiologically heterogeneous neurological disorders typically associated with lesions located in the language dominant parietal and frontal region. The condition is characterized by a hesitant, incomplete, imprecise or even illegible graphomotor output. Letter formation cannot be attributed to sensorimotor, extrapyramidal or cerebellar dysfunction affecting the writing limb. Detailed clinical, neurocognitive, neurolinguistic and (functional) neuroimaging characteristics of three unique cases are reported that developed AA following a thalamic stroke. In marked contrast to impaired handwriting, non-handwriting skills, such as oral spelling, were hardly impaired. Quantified Tc-99m ECD SPECT consistently showed a decreased perfusion in the anatomoclinically suspected prefrontal regions. The findings suggest crucial involvement of the anterior (and medial) portion of the left thalamus within the neural network subserving the graphomotor system. Functional neuroimaging findings seem to indicate that AA after focal thalamic damage represents a diaschisis phenomenon.
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PMID:Apraxic agraphia following thalamic damage: Three new cases. 2646 Sep 84