Funktionelle Organisation expressiver Sprache bei der mesialen Temporallappenepilepsie: fMRT Studie zum Vergleich hippocampaler Aktivierung bei freier Wortproduktion gegenüber Standard-Wortflüssigkeitsaufgaben

内侧颞叶癫痫表达语言的功能组织：功能磁共振成像研究比较自由词产生过程中海马的激活与标准言语流利任务期间的海马激活

• 批准号: 202263786
• 负责人: Dr. Anja Haag
• 金额: --
• 依托单位: Queen Square Institute of Neurology
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2011-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/202263786?language=en
• 关键词: Funktionelle; Organisation; expressiver; Sprache; bei

Language is almost unique to the human species. It is of major relevance in every day life and social functioning. Verbal communication abilities crucially influence quality of life. Therefore, language is of high interest in clinical neuroscience. Expressive language function is classically associated with frontal lobe cortex (e.g. Broca`s area) but recent studies also point towards functional relevance of temporal lobe structures (e.g. the hippocampus). Mesial temporal lobe epilepsy (mTLE) constitutes a lesion model for hippocampal function. This fMRI project aims to study word fluency as an expressive language function in mTLE patients. Word fluency is usually investigated with word generation to a given initial letter (phonemic fluency) or to a given category (semantic fluency). However, free, unrestricted word generation has shown hippocampal activation on fMRI in healthy volunteers. This hippocampal activation was attenuated in schizophrenia, which is accompanied (among other pathology) by structural abnormalities of temporal cortex. Patients with mTLE of the left hemisphere, which is usually language dominant, share further characteristics with schizophrenia patients: Both exhibit verbal memory deficits and have a higher probability of atypical (bilateral or right hemispheric) language dominance. Atypical language dominance is considered a result of functional reorganization processes due to neural plasticity. What leads to such reorganisation is not yet clearly understood. This study intends to add substantial knowledge about the role of the hippocampus in expressive language and aims to better characterize determinants of cortical language representation in patients with specific brain lesions. Language fMRI is frequently applied to patients who are candidates for epilepsy surgery to preoperatively identify eloquent cortex. As a clinical impact, results of the proposed study shall contribute to improve current paradigms for fMRI language assessment.

语言几乎是人类所独有的。它与日常生活和社会功能密切相关。语言沟通能力对生活质量有着至关重要的影响。因此，语言在临床神经科学中具有很高的兴趣。表达性语言功能通常与额叶皮层（例如布罗卡区）相关，但最近的研究也指出了颞叶结构（例如海马体）的功能相关性。内侧颞叶癫痫（mTLE）构成了海马功能的损伤模型。本研究旨在探讨颞叶癫痫患者的词汇流畅性作为一种表达性语言功能。单词流畅性通常是通过对给定首字母（音素流畅性）或给定类别（语义流畅性）的单词生成来研究的。然而，在健康志愿者的fMRI上，自由、无限制的单词生成显示了海马体的激活。这种海马激活在精神分裂症中减弱，这是伴随着（在其他病理学中）颞叶皮层的结构异常。左半球的mTLE患者通常是语言优势，与精神分裂症患者有更多的共同特征：两者都表现出言语记忆缺陷，并且具有更高的非典型（双侧或右半球）语言优势的可能性。非典型语言优势被认为是由于神经可塑性的功能重组过程的结果。导致这种重组的原因尚不清楚。本研究旨在增加大量的知识，海马在表达语言的作用，并旨在更好地表征特定脑损伤患者的皮质语言表征的决定因素。语言功能磁共振成像经常被应用于癫痫手术的候选人，以术前识别功能皮层。作为一个临床影响，拟议的研究结果将有助于改善目前的范式功能磁共振成像语言评估。