Analysis of human cortical networks during sustained visuospatial attention

持续视觉空间注意力过程中人类皮质网络的分析

• 批准号: 7472171
• 负责人: MICHAEL A SILVER
• 金额: $ 19.13万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2010-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7472171
• 关键词: Acetylcholine; Alzheimer' s Disease; Anatomy; Animals; Area; Aricept; Attention; Attention Deficit Disorder; Behavior; Behavioral; Brain; Brain Diseases; Brain region; Cholinergic Agents; Cholinesterase Inhibitors; Cognitive; Communication; Coupling; Data; Exhibits; Expectancy; Failure; Functional Magnetic Resonance Imaging; Goals; Human; Human body; Impairment; Individual; Investigation; Location; Magnetic Resonance Imaging; Maps; Measures; Mediating; Methods; Microelectrodes; Multivariate Analysis; Names; Neural Pathways; Neurotransmitters; Numbers; Parietal; Parietal Lobe; Pathway interactions; Perception; Performance; Pharmaceutical Preparations; Photic Stimulation; Physiological; Physiology; Play; Psyche structure; Public Health; Reaction Time; Role; Sensory; Series; Signal Transduction; Stimulus; Symptoms; Synapses; System; Task Performances; Testing; Thinking; Time; Visual; Visual Cortex; Visual Fields; Visual Perception; Visual attention; Visuospatial; area V1; attentional modulation; basal forebrain; base; cholinergic; clinically relevant; donepezil; human subject; improved; intraparietal sulcus; nervous system disorder; neuroimaging; novel; relating to nervous system; research study; response; transmission process; visual stimulus

DESCRIPTION (provided by applicant): The long-term objectives of this project are 1) to identify functional networks of cortical areas in the human brain that subserve visual spatial attention, and 2) to determine the effects of manipulation of synaptic levels of acetylcholine on the physiology of these functional networks. Humans employ spatial attention to select portions of the visual field that are most relevant for their current behavioral goals. If a visual stimulus appears in an attended location, observers perceive the stimulus more accurately than if the same stimulus is presented to an unattended location. This improvement in perception is thought to be due to attention signals that are transmitted by parietal cortex to early visual cortical areas. However, the neural pathways that carry these attention signals to visual cortex are largely unknown. Acetylcholine is a neurotransmitter that plays an important role in attention networks in the brain. Drugs that prolong the synaptic actions of endogenous acetylcholine (cholinesterase inhibitors) improve performance on attention tasks in human subjects. However, very little is known regarding the physiological effects of acetylcholine on attention signals. The fundamental importance of attention for behavior is demonstrated by the many brain disorders characterized by compromised attention networks. Attention abnormalities are the central symptom in Attention Deficit Disorder. Additionally, many of the mental impairments that have been associated with Alzheimer's disease can be traced to a failure of attention. We will use neuroimaging (functional magnetic resonance imaging, or fMRI) to measure the activity in defined brain areas while subjects are performing attention-demanding tasks. Changes in activity in these areas during task performance will be compared across the identified brain areas, using coherency and partial coherency methods recently developed by our group, to characterize attention pathways and flow of attention signals to visual cortex. In addition, subjects will be administered donepezil (trade name: Aricept), a cholinesterase inhibitor and Alzheimer's medication that enhances attention. The effects of this drug on the functional networks underlying attention will be measured. PUBLIC HEALTH RELEVANCE We will use magnetic resonance imaging (MRI) to measure brain activity in healthy human subjects while they are maintaining attention at a defined visual location. The activity in many brain areas will be compared to identify the network of brain regions that is responsible for visual attention. In addition, the subjects will be administered donepezil, an Alzheimer's medication known to improve attention, and we will measure the effects of this drug on brain activity and the communication between brain areas during sustained attention.

描述（由申请人提供）：该项目的长期目标是1)确定人脑皮层区域的功能网络，这些功能网络为视觉空间注意力提供服务，2)确定乙酰胆碱突触水平的操纵对这些功能网络的生理影响。人类利用空间注意力来选择视野中与当前行为目标最相关的部分。如果一个视觉刺激出现在有人在场的位置，观察者对刺激的感知比同样的刺激出现在无人在场的位置更准确。这种知觉的改善被认为是由于注意信号由顶叶皮层传递到早期视觉皮质区。然而，将这些注意力信号传递到视觉皮层的神经通路在很大程度上是未知的。乙酰胆碱是一种神经递质，在大脑的注意力网络中起着重要作用。延长内源性乙酰胆碱（胆碱酯酶抑制剂）突触作用的药物可改善人类受试者的注意力任务表现。然而，关于乙酰胆碱对注意信号的生理作用知之甚少。许多以注意力网络受损为特征的脑部疾病证明了注意力对行为的根本重要性。注意异常是注意缺陷障碍的主要症状。此外，许多与阿尔茨海默病相关的精神障碍都可以追溯到注意力不集中。我们将使用神经成像（功能性磁共振成像或fMRI）来测量受试者在执行注意力要求任务时大脑特定区域的活动。在任务执行过程中，这些区域的活动变化将在确定的大脑区域之间进行比较，使用我们小组最近开发的一致性和部分一致性方法，以表征注意力通路和注意信号流向视觉皮层。此外，受试者将被给予多奈哌齐（商品名：Aricept），一种胆碱酯酶抑制剂和阿尔茨海默病药物，以提高注意力。这种药物对潜在注意力的功能网络的影响将被测量。我们将使用磁共振成像（MRI）来测量健康人类受试者在特定视觉位置保持注意力时的大脑活动。将对许多大脑区域的活动进行比较，以确定负责视觉注意力的大脑区域网络。此外，研究对象还将服用多奈哌齐，这是一种治疗阿尔茨海默病的药物，可以提高注意力。我们将测量这种药物对大脑活动的影响以及持续注意力期间大脑各区域之间的交流。