Bobholz J A, Rao S M, Lobeck L, Elsinger C, Gleason A, Kanz J, Durgerian S, Maas E
Department of Neurology, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
Neurology. 2006 Nov 14;67(9):1640-5. doi: 10.1212/01.wnl.0000242885.71725.76.
To determine whether memory loss in patients with multiple sclerosis (MS) results from faulty encoding or retrieval, we correlated extent of T2-weighted lesion involvement with brain activation patterns on fMRI scans obtained while patients performed a verbal episodic memory task.
We performed a neurologic examination, neuropsychological testing, and an event-related fMRI scan on 36 patients with relapsing-remitting MS. In addition, we obtained T2-weighted structural MRI scans to measure lesion volume. We performed a regression analysis to examine the association between lesion volume and regional brain activation.
Increasing lesion volume correlated with increasing magnitude of brain activation, primarily in the left frontal and parietal association cortices. Significant correlations of function with lesion volume were primarily observed during the memory retrieval phase of the task.
These results extend previous fMRI studies in multiple sclerosis (MS) by demonstrating an association between greater disease burden and increased neural recruitment during episodic memory. In addition, the stronger correlations observed between lesion volume and brain activation during retrieval than encoding would suggest that retrieval processes are more affected by MS-related cerebral pathology.
为了确定多发性硬化症（MS）患者的记忆丧失是由错误编码还是检索引起的，我们将T2加权病变累及范围与患者执行言语情景记忆任务时获得的功能磁共振成像（fMRI）扫描上的脑激活模式进行了关联分析。
我们对36例复发缓解型MS患者进行了神经学检查、神经心理学测试和事件相关fMRI扫描。此外，我们获得了T2加权结构磁共振成像扫描以测量病变体积。我们进行了回归分析以检查病变体积与局部脑激活之间的关联。
病变体积增加与脑激活程度增加相关，主要在左侧额叶和顶叶联合皮质。功能与病变体积的显著相关性主要在任务的记忆检索阶段观察到。
这些结果扩展了先前关于多发性硬化症（MS）的fMRI研究，通过证明更大的疾病负担与情景记忆期间神经募集增加之间的关联。此外，在检索期间观察到的病变体积与脑激活之间的相关性比编码期间更强，这表明检索过程受MS相关脑病理学的影响更大。
