Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
Department of Neurology, Medical University of Vienna, Vienna, Austria.
PLoS One. 2022 Feb 22;17(2):e0264349. doi: 10.1371/journal.pone.0264349. eCollection 2022.
Impairment of cognitive functions is commonly observed in temporal lobe epilepsy (TLE). The aim of this study was to assess visuospatial memory functions and memory-related networks using an adapted version of Roland's Hometown Walking (RHWT) functional MRI (fMRI) task in patients with TLE.
We used fMRI to study activation patterns based on a visuospatial memory paradigm in 32 TLE patients (9 right; 23 left) and also within subgroups of lesional and non-lesional TLE. To test for performance, a correlational analysis of fMRI activation patterns and out-of-scanner neuropsychological visuospatial memory testing was performed. Additionally, we assessed memory-related networks using functional connectivity (FC).
Greater contralateral than ipsilateral mesiotemporal (parahippocampal gyrus/hippocampus) activation was observed in left (n = 23)/right (n = 9) TLE. In lesional left TLE (n = 17), significant activations were seen in right more than left mesiotemporal areas (parahippocampal gyrus), while non-lesional left TLE patients (n = 6) showed significant bilateral (left>right) activations in mesiotemporal structures (parahippocampal gyrus). In left TLE, visuospatial cognitive testing correlated with fMRI activations in left (parahippocampal gyrus) and right mesiotemporal structures (hippocampus), characterized by greater fMRI activation being associated with better memory scores. In right TLE, higher scores in visuospatial memory testing were associated with greater fMRI activations in left and right insular regions. FC patterns of memory-related networks differ in right and left TLE.
While TLE in general leads to asymmetrical mesiotemporal activation, lesion-induced and non-lesional TLE patients reveal different memory fMRI activation patterns. In right TLE, insular regions try to compensate for impaired right mesiotemporal structures during the performance of visuospatial tasks. Underlying functional visuospatial memory networks differ in right and left TLE.
认知功能障碍在颞叶癫痫（TLE）中很常见。本研究旨在通过 Roland 家乡步行（RHWT）功能磁共振成像（fMRI）任务的改编版本，评估 TLE 患者的视空间记忆功能和与记忆相关的网络。
我们使用 fMRI 研究了 32 名 TLE 患者（9 名右侧；23 名左侧）基于视空间记忆范式的激活模式，还在病变和非病变 TLE 的亚组中进行了研究。为了测试表现，我们对 fMRI 激活模式与扫描仪外神经心理学视空间记忆测试进行了相关分析。此外，我们还使用功能连接（FC）评估了与记忆相关的网络。
左（n = 23）/右（n = 9）TLE 患者中观察到对侧间脑（海马旁回/海马）激活明显大于同侧。在病变性左侧 TLE（n = 17）中，右侧间脑区域（海马旁回）的激活明显大于左侧，而非病变性左侧 TLE 患者（n = 6）在间脑结构（海马旁回）中显示出明显的双侧（左>右）激活。在左侧 TLE 中，视空间认知测试与左侧（海马旁回）和右侧间脑结构（海马）的 fMRI 激活相关，其特征是 fMRI 激活越大，记忆分数越高。在右侧 TLE 中，视空间记忆测试得分越高，与左侧和右侧岛叶区域的 fMRI 激活越高相关。与记忆相关的网络的 FC 模式在右侧和左侧 TLE 中不同。
虽然 TLE 通常导致不对称的间脑激活，但病变诱导和非病变 TLE 患者显示出不同的记忆 fMRI 激活模式。在右侧 TLE 中，在执行视空间任务时，岛叶区域试图补偿右侧间脑结构受损。右侧和左侧 TLE 中存在不同的功能视空间记忆网络。
