MODELS OF NORMAL & POSTSTROKE HEMISPHERIC INTERACTIONS

正常模型

• 批准号: 6097002
• 负责人: JAMES A REGGIA
• 金额: $ 28.02万
• 依托单位: UNIV OF MARYLAND, COLLEGE PARK
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-20 至 2005-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6097002
• 关键词: association learning; brain interhemispheric activity; cerebral dominance; computational neuroscience; corpus callosums; disease /disorder model; experimental brain lesion; human data; interhemispheric transfer; learning transfer; neural plasticity; stroke

Current understanding of the origins of cerebral specialization and of hemispheric interactions is fairly limited. For example, it is unclear which recognized cortical asymmetries lead to lateralization, whether the net influence of one hemisphere on the other is excitatory or inhibitory, and to the extent to which the intact contralateral hemisphere contributes to recovery following a cortical lesion such as a stroke. The long-term goal of this work is to gain a better understanding of these issues by developing and studying neural models of emergent hemispheric lateralization and of hemispheric interactions as those models recover from simulated cortical lesions. The models consist of networks of paired left and right cortical regions connected by a simulated corpus callosum. The specific aims are: 1. to test the hypothesis that models have excitatory callosal connections and indirect interhemispheric competition can better explain data from biological/behavioral experiments than previous models; 2. to determine how learning one behavioral task can influence the direction/extent of another task's lateralization; 3. to determine how multiple underlying hemispheric asymmetries in a single model interact, altering the direction/extent of lateralization produced by each alone; and 4. to examine lateralization and post-lesion hemispheric interactions in a neurobiologically-grounded model of associative word learning that is directly comparable to behavioral, clinical and functional imaging data. This is the first systematic attempt to better understand cerebral specialization and transcallosal diaschisis using computational models. The results will directly relate to ongoing experimental work, have important implications for current theories of the mechanisms underlying hemispheric functional asymmetries and post-stroke recovery, and may suggest new therapeutic concepts for stroke patients.

目前对大脑特化和半球相互作用的起源的理解相当有限。 例如，目前尚不清楚哪种公认的皮质不对称导致偏侧化，一个半球对另一个半球的净影响是兴奋性还是抑制性，以及在皮质损伤（如中风）后，完整的对侧半球在多大程度上有助于恢复。 这项工作的长期目标是获得更好地了解这些问题，通过开发和研究神经模型的紧急半球侧化和半球的相互作用，因为这些模型从模拟皮层病变恢复。 这些模型由通过模拟胼胝体连接的成对左右皮质区域的网络组成。 具体目标是：1.检验模型具有兴奋性胼胝体连接和间接的半球间竞争的假设比以前的模型更好地解释了来自生物/行为实验的数据; 2.确定学习一个行为任务如何影响另一个任务的侧化方向/程度; 3.确定单个模型中的多个潜在半球不对称如何相互作用，从而改变由每个单独产生的侧化的方向/程度;以及4.研究偏侧化和损伤后半球的相互作用，在一个神经生物学接地模型的联想词学习，是直接可比的行为，临床和功能成像数据。 这是第一个系统的尝试，以更好地了解大脑的专业化和跨胼胝体神经联系不能使用计算模型。 这些结果将直接关系到正在进行的实验工作，有重要的意义，目前的理论基础半球功能不对称和中风后恢复的机制，并可能提出新的治疗概念，中风患者。