Neuroimaging Of Frontal Lobe Functioning During Cognitio

认知过程中额叶功能的神经影像学

• 批准号: 6823942
• 负责人: Karen FAITH Berman
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF MENTAL HEALTH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6823942
• 关键词: bioimaging /biomedical imaging; brain circulation; brain imaging /visualization /scanning; clinical research; cognition; frontal lobe /cortex; human subject; memory; neural information processing; neuropsychology; positron emission tomography; verbal behavior

Using functional neuroimaging to determine local neuronal activity, we have found that normal subjects performing tasks involving working memory use a cortical network including dorsolateral prefrontal cortex, inferior parietal lobule, and inferior temporo-occipital cortex. In other tasks related to prefrontal cortex, we have shown, with word generation (verbal fluency) tasks that semantic and phonologic cues activate similar brain regions including anterior cingulate, left frontal cortex, thalamus and cerebellum, but subtle differences exist between them that are consistent with the lesion literature. In a study of cognitive activation in normal aging we found that neurophysiological changes were context dependent. That is, apparent changes over the life span differed in different tasks, depending on the role of the particular neural system for the particular task. In regions where physiological activity is normally suppressed when young subjects perform the tasks older subjects activate more, and, moreover, the more they activate (or fail to suppress), the worse they perform on the tasks. In other areas, where physiological activity is normally increased in young people performing the tasks, older subjects activate less; and the less they activate these regions, the more impaired their performance. We have also confirmed that large-scale changes in brain activity at the systems level (accompanying nonlinear changes in behavior) follow predictions from nonlinear dynamical theory, and we have defined discriminable frontal lobe regions (lateral prefrontal cortex and anterior cingulate cortex) that subserve different cognitive components in switching between tasks (overcoming the residual inhibition of previous task demands and initiating a new task, respectively). We have also shown that the neural system patterns activated in individual healthy subjects reflect their levels of performance and cognitive strategies (verbal versus spatial) on a working memory task.

使用功能性神经成像来确定局部神经元活性，我们发现执行涉及工作记忆的任务的正常受试者使用皮层网络，包括背外侧前额叶皮层，下层叶叶叶下叶和下颞叶枕皮层。在与前额叶皮层相关的其他任务中，我们已经表明，语言和语音线索的单词产生（语言流利性）任务激活了相似的大脑区域，包括前扣带回，左侧皮层，thalamus和小脑，但它们之间存在微妙的差异，它们与《病时代文献》一致。在对正常衰老的认知激活的研究中，我们发现神经生理学的变化取决于上下文。也就是说，在不同任务中，生命周期的明显变化有所不同，这取决于特定神经系统在特定任务中的作用。在年轻受试者执行较旧受试者的任务时，通常会抑制生理活动的区域中，他们激活越多（或无法抑制），他们对任务的执行越糟。在其他领域，在执行任务的年轻人中通常会增加生理活动的其他领域，较老的受试者激活较少。而且他们激活这些地区的越少，其性能就越受损。我们还已经证实，系统级别的大脑活动的大规模变化（伴随行为的非线性变化）遵循非线性动力学理论的预测，我们已经定义了可区分的额叶区域（定义的额叶皮层和前额叶皮层和前缘皮层的侧向皮层），这些区域是在任务和任务之间的启动中的不同认知组成部分（克服任务之间的不同认知组件），以克服任务，以克服任务的任务和任务。 分别）。我们还表明，在单个健康受试者中激活的神经系统模式反映了他们在工作记忆任务上的表现和认知策略（口头与空间）的水平。