Powell H W Robert, Parker Geoff J M, Alexander Daniel C, Symms Mark R, Boulby Philip A, Wheeler-Kingshott Claudia A M, Barker Gareth J, Koepp Matthias J, Duncan John S
Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, Queen Square, London, WC1N 3BG, UK.
Neuroimage. 2007 May 15;36(1):209-21. doi: 10.1016/j.neuroimage.2007.02.028. Epub 2007 Feb 28.
Functional magnetic resonance imaging (fMRI) in patients with temporal lobe epilepsy (TLE) has demonstrated reorganisation of language functions with greater involvement of the non-dominant hemisphere. The structural brain connections supporting this atypical language dominance have not previously been identified. We performed fMRI of language functions and imaging of white matter connections using MR tractography in 14 patients with unilateral TLE and hippocampal sclerosis and 10 controls. Verb generation and reading comprehension paradigms were used to define functional regions which were used to generate starting regions for tractography. Controls and right TLE patients had a left-lateralised pattern of both language-related activations and the associated structural connections. Left TLE patients showed more symmetrical language activations, along with reduced left hemisphere and increased right hemisphere structural connections. Subjects with more lateralised functional activation had also more highly lateralised connecting pathways. We provide evidence for structural reorganisation of white matter tracts that reflects the altered functional language lateralisation in left TLE patients. The combination of fMRI and tractography offers a promising tool for studying the reorganisation of language functions in many neurological conditions and may prove useful in predicting language deficits following temporal lobe surgery.
功能性磁共振成像（fMRI）显示，颞叶癫痫（TLE）患者的语言功能发生了重组，非优势半球的参与程度更高。此前尚未确定支持这种非典型语言优势的脑结构连接。我们对14例单侧TLE和海马硬化患者及10名对照者进行了语言功能的fMRI检查和使用磁共振纤维束成像的白质连接成像。采用动词生成和阅读理解范式来定义功能区，这些功能区被用于生成纤维束成像的起始区域。对照者和右侧TLE患者在语言相关激活及相关结构连接方面均呈现左侧化模式。左侧TLE患者表现出更对称的语言激活，同时左侧半球结构连接减少，右侧半球结构连接增加。功能激活更具侧化的受试者其连接通路的侧化程度也更高。我们为白质束的结构重组提供了证据，这种重组反映了左侧TLE患者语言功能侧化的改变。fMRI与纤维束成像相结合为研究多种神经疾病中的语言功能重组提供了一种很有前景的工具，并且可能在预测颞叶手术后的语言缺陷方面证明有用。
