title: Contributions of bilateral white matter to chronic aphasia symptoms as assessed by diffusion tensor MRI.
abstract: Language reorganisation following stroke has been studied widely. However, while studies of brain activation and grey matter examined both hemispheres, studies of white matter changes have mostly focused on the left hemisphere. Here we examined the relationship between bilateral hemispheric white matter and aphasia symptoms. 15 chronic stroke patients with aphasia and 18 healthy adults were studied using Diffusion Weighted Imaging data. By applying histogram analysis, Tract-Based Spatial Statistics, tractography and lesion-tract overlap methods, it was found that damage to the left hemisphere in general, and to the arcuate fasciculus in particular, correlated with impairments on word repetition, object naming, sentence comprehension and homophone and rhyme judgement. However, no such relationship was found in the right hemisphere. It is suggested that while some language function in aphasia can be explained by damage to the left arcuate fasciculus, it cannot be explained by looking at the contra-lesional tract.
authors.affiliation: Department of Clinical Neurosciences, University of Cambridge, United Kingdom; Cognitive Neuroscience and Neuropsychiatry Section, UCL Institute of Child Health, United Kingdom. Electronic address: sharon.geva@cantab.net.
authors.forename: Sharon
authors.initials: S
authors.lastname: Geva
authors.affiliation: MRC Cognition and Brain Sciences Unit, Cambridge, United Kingdom.
authors.forename: Marta M
authors.initials: MM
authors.lastname: Correia
authors.affiliation: Department of Clinical Neurosciences, University of Cambridge, United Kingdom.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Warburton
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001037:Aphasia / Q000209:etiology / Q000503:physiopathology*; D001921:Brain / Q000503:physiopathology; D001931:Brain Mapping; D016022:Case-Control Studies; D054022:Cerebrum / Q000503:physiopathology; D032882:Comprehension; D038524:Diffusion Magnetic Resonance Imaging; D056324:Diffusion Tensor Imaging; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007802:Language; D008297:Male; D008875:Middle Aged; D020521:Stroke / Q000150:complications / Q000503:physiopathology; D066127:White Matter / Q000503:physiopathology*
keywords: Arcuate fasciculus; Diffusion Tensor Imaging; Language; Stroke