NEUROPSYCHOLOGICAL AND COGNITIVE STUDIES IN EPILEPSY

我们一直在进行语言组织的成像研究 正常对照组和癫痫患者。使用正电子发射 体层摄影术(PET)，激活脑血流(CBF)与 单词和对象识别，听觉理解，以及音素，单词， 和句子的产生在大脑中是局部的。对这些问题的研究 正常功能是评估癫痫发作效果的基础 由颞叶和其他部位引起的认知过程障碍 大脑结构。在记忆研究中，大脑的失活 提取过程中的血流量反映了早期编码的效果。 去激活的区域是那些参与初始 刺激的处理。在视觉设计识别任务中，我们发现 右侧初级视皮层失活。在听音过程中 再认任务时，双侧上脑血流量相对减少 和中颞区。我们还评估了一项经典学习 使用眨眼条件反射的范例。我们发现学习是特定的 先前动物研究涉及的区域的脑血流量增加， 包括小脑、基底节、额叶皮质和海马体。 在左侧颞叶病灶的患者中，PET显示功能重组 语言处理方面的知识。硬膜下刺激、正电子发射计算机断层扫描和 磁共振成像(MRI)是使用数字图像进行集成的 加工技术。结合刺激和正电子发射计算机断层扫描数据，我们可以 认知功能激活与认知障碍关系的研究 活动，并形成更准确的组织概念 大脑功能。这些研究将阐明区域的功能 例如基本的颞叶语言区，这是临床上的 在计划对失控癫痫进行手术时的重要性。数位 使用信号处理技术对PET、CT、MRI和硬膜下进行对准 电极位置。我们发现PET-CBF与 使用多个不同功能的硬膜下刺激标测 测试。这一结果显示了无创术前检查的实用性。 脑功能图，也证明了脑功能图 干扰和激活研究。我们发现有重要的参与 基本的时间语言区域，这可能解释了意外 术后缺陷，在PET激活研究中。在硬膜下 标测，刺激基础颞区中断隐含 记忆启动。通过对儿童进行功能磁共振成像，我们发现左侧脑内信号增强 额叶和颞叶下部。这种非侵入性技术可以 被用来偏侧化讲话。

We have been performing imaging studies of language organization in normal controls and patients with epilepsy. Using positron emission tomography (PET), activation of cerebral blood flow (CBF) associated with word and object recognition, auditory comprehension, and phoneme, word, and sentence production are localized in the brain. Studies of these functions in normals form the basis for evaluating the effect of seizure disorders on cognitive processes subserved by temporal lobe and other cerebral structures. In studies of memory, deactivation of cerebral blood flow during retrieval reflects the effects of earlier encoding. The deactivated regions are those which are engaged in the initial processing of stimuli. During a visual design recognition task, we found deactivation of right primary visual cortex. During an auditory recognition task, there was a relative CBF decrease in bilateral superior and middle temporal regions. We also evaluated a classical learning paradigm using eyeblink conditioning. We found learning specific increases in CBF in regions previously implicated in animal studies, including cerebellum, basal ganglia, frontal cortex, and hippocampus. In patients with left temporal foci, PET showed functional reorganization of language processing. Data from subdural stimulation, PET, and magnetic resonance imaging (MRI) are integrated using digital image processing techniques. The combined stimulation and PET data allow us to study the relationship between activation and disruption of cognitive activity, and to form more accurate concepts of the organization of cerebral function. These studies will elucidate the function of regions such as the basal temporal language area, which are of clinical importance when surgery for uncontrolled seizures is planned. Digital signal processing techniques are used to align PET, CT, MRI, and subdural electrode positions. We found a high concordance between PET-CBF and subdural stimulation mapping using a number of different functional tests. This result shows the practicality of noninvasive preoperative functional brain mapping, and also demonstrates the close correlation of disruption and activation studies. We have found significant involvement of the basal temporal language area, which may explain unexpected postoperative deficits, in PET activation studies. During subdural mapping, stimulation of the basal temporal region disrupted implicit memory priming. Using fMRI in children, we found increased signal in left inferior frontal and temporal regions. This noninvasive technique can be used to lateralize speech.