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

Stroke patients with nonfluent aphasia tend to be younger than fluent aphasics. We investigated whether this difference was due to an age-related change in the anatomicofunctional organisation of language areas or to an age-dependent variation on the distribution of infarct localisation. From a hospital prospective stroke database we selected those patients who suffered an ischaemic stroke with at least one non-lacunar infarct demonstrated by computed tomography (n = 423 patients). We retrieved information on language disturbance in the acute phase (no aphasia, non-fluent aphasia, fluent aphasia) and on infarct localisation by CT. Non-fluent aphasia predominated in young (aged < 51 years) patients while in elderly patients (aged > 70 years) the opposite was found (chi 2 = 8.03; P = 0.005). Posterior infarcts were also more frequent in elderly patients (chi 2 = 9.9; P = 0.002). There were 27 atypical cases (patients with lesions on language areas without aphasia) and 14 aphasics with atypical infarct localisation (9 fluent aphasics with anterior lesions and 5 non-fluent aphasics with posterior lesions). The proportions of atypical cases, their infarct location or fluency type were not influenced by age. It was concluded that the predominance of fluent aphasia in older patients was related to the higher proportion of posterior infarcts in these patients. The hypothesis of age-related changes in the anatomico-functional organisation of language areas was not supported by the present data.
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PMID:Aphasia type, age and cerebral infarct localisation. 930 57

Non-fluent aphasia implies a relatively straightforward neurological condition characterized by limited speech output. However, it is an umbrella term for different underlying impairments affecting speech production. Several studies have sought the critical lesion location that gives rise to non-fluent aphasia. The results have been mixed but typically implicate anterior cortical regions such as Broca's area, the left anterior insula, and deep white matter regions. To provide a clearer picture of cortical damage in non-fluent aphasia, the current study examined brain damage that negatively influences speech fluency in patients with aphasia. It controlled for some basic speech and language comprehension factors in order to better isolate the contribution of different mechanisms to fluency, or its lack. Cortical damage was related to overall speech fluency, as estimated by clinical judgements using the Western Aphasia Battery speech fluency scale, diadochokinetic rate, rudimentary auditory language comprehension, and executive functioning (scores on a matrix reasoning test) in 64 patients with chronic left hemisphere stroke. A region of interest analysis that included brain regions typically implicated in speech and language processing revealed that non-fluency in aphasia is primarily predicted by damage to the anterior segment of the left arcuate fasciculus. An improved prediction model also included the left uncinate fasciculus, a white matter tract connecting the middle and anterior temporal lobe with frontal lobe regions, including the pars triangularis. Models that controlled for diadochokinetic rate, picture-word recognition, or executive functioning also revealed a strong relationship between anterior segment involvement and speech fluency. Whole brain analyses corroborated the findings from the region of interest analyses. An additional exploratory analysis revealed that involvement of the uncinate fasciculus adjudicated between Broca's and global aphasia, the two most common kinds of non-fluent aphasia. In summary, the current results suggest that the anterior segment of the left arcuate fasciculus, a white matter tract that lies deep to posterior portions of Broca's area and the sensory-motor cortex, is a robust predictor of impaired speech fluency in aphasic patients, even when motor speech, lexical processing, and executive functioning are included as co-factors. Simply put, damage to those regions results in non-fluent aphasic speech; when they are undamaged, fluent aphasias result.
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PMID:Damage to the anterior arcuate fasciculus predicts non-fluent speech production in aphasia. 2413 92