Methods for Dynamic Functional Imaging

动态功能成像方法

• 批准号: 7895518
• 负责人: ANTHONY M NORCIA
• 金额: $ 37.87万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7895518
• 关键词: Adult; Anterior; Appearance; Area; Attention; Automobile Driving; Behavior; Behavioral; Brain; Brain imaging; Clinical; Complex; Computer Simulation; Cues; Data; Dementia; Dependence; Development; Diagnosis; Discrimination; Disease; Disease Management; Electroencephalography; Environment; Event; Feedback; Functional Imaging; Functional Magnetic Resonance Imaging; Future; Goals; Head; Image; Individual; Lateral; Learning; Link; Macaca; Maps; Measurement; Measures; Memory; Methods; Modeling; Motor; Neurons; Perception; Performance; Play; Population; Prefrontal Cortex; Process; Protocols documentation; Role; Sensory; Shapes; Signal Transduction; Source; Specificity; Staging; Stimulus; Stroke; Structure; Surface; Techniques; Temporal Lobe; Testing; Time; Traumatic Brain Injury; Vision; Visual; Visual Perception; Visual impairment; Visual system structure; base; brain malformation; cognitive function; executive function; expectation; experience; extrastriate visual cortex; frontal lobe; imaging modality; novel; object recognition; operation; public health relevance; reconstruction; research study; response; retinotopic; sample fixation; visual control; visual memory; visual process; visual processing

DESCRIPTION (provided by applicant): The fundamental goal of perception is to infer the structure of the world through an interpretation of temporal and spatial regularities in sensory stimulation that map onto structures in the environment such as objects and surfaces. The goal of this proposal is to trace the emergence of low-level object processing operations as they evolve in time and cortical area and to study how rapid, on-line learning or adaptation modifies these responses. We propose to study the mechanisms by which the visual system segments the visual scene into objects and surfaces and how it adapts its responses to stimuli with varying levels of temporal regularity using a combination of EEG source-imaging and functional MRI techniques in normal adults. In the first Aim we will study how attention interacts with low-level mechanisms involved in figure-ground segmentation. A novel, multi-input stimulation and analysis method will be used to separate response to figures and their backgrounds. In the second Aim, we will determine how temporal predictability shapes the accuracy behavioral shape discrimination by correlating behavioral performance with activity in visual and control areas that occurs before the presentation of predictable targets. A second goal is to determine if anticipatory evoked activity made in response to temporally regular stimuli can occur implicitly. The third Aim will record responses to predictable and unpredictable stimuli of varying degrees of salience. Anticipatory activity will be isolated by subtracting reconstructions of the evoked response derived from random stimuli from those measured with temporally regular stimuli over a range of stimulus salience. These data will be used to test the hypothesis that anticipatory activity is generated in prefrontal cortex and produces its largest effects in target areas of occipital/occipital temporal cortex for low salience stimuli. PUBLIC HEALTH RELEVANCE The tasks we will study require integrated activity throughout the visual hierarchy, in executive control areas of pre-frontal cortex and in areas responsible for sensory motor integration and motor response. The methods we develop to link brain activity and behavior at each of these levels will be relevant to understanding and managing disorders of visual processing, visual memory, visuo-motor integration and motor execution. Because the methods are non-invasive they can be applied directly to clinical populations in future studies of Cortical Visual Impairment, traumatic brain injury, stroke, dementia and congenital brain malformations. These disorders frequently compromise visual processing and each often involves significant compromise of motor and cognitive functions. Careful adaptation of the protocols that will be developed in this proposal may provide information relevant to the diagnosis and management of these disorders.

描述(申请人提供)：感知的基本目标是通过解释感觉刺激中映射到环境中的结构(如物体和表面)的时间和空间规律来推断世界的结构。这项建议的目标是追踪低水平物体加工操作的出现，因为它们在时间和大脑皮层区域演变，并研究快速的在线学习或适应如何改变这些反应。我们建议结合脑电源成像和功能磁共振技术，研究视觉系统将视觉场景分割为对象和表面的机制，以及它如何适应不同程度的时间规律性刺激的反应。在第一个目标中，我们将研究注意如何与图形-背景分割中涉及的低水平机制相互作用。将使用一种新颖的、多输入的刺激和分析方法来分离对图形及其背景的响应。在第二个目标中，我们将通过将行为表现与呈现可预测目标之前在视觉和控制区域发生的活动相关联，来确定时间可预测性如何塑造行为形状辨别的准确性。第二个目标是确定对时间规律刺激做出反应的预期诱发活动是否可以隐含地发生。第三个目标将记录对不同程度的显著程度的可预测和不可预测的刺激的反应。预期活动将通过将随机刺激产生的诱发反应的重建减去在一定刺激显著范围内用时间规则刺激测量的反应的重建来分离。这些数据将被用来检验这一假设，即预期活动在前额叶皮质产生，并在枕叶/枕叶颞叶皮质的目标区域产生最大影响，以获得低显著刺激。公共卫生相关性我们将研究的任务需要在整个视觉层级、前额叶皮质的执行控制区以及负责感觉运动整合和运动反应的区域进行整合活动。我们开发的将大脑活动和行为在每个水平上联系起来的方法将与理解和管理视觉处理、视觉记忆、视觉-运动整合和运动执行的障碍有关。由于这些方法是非侵入性的，它们可以直接应用于临床人群，在未来的皮质视觉障碍、创伤性脑损伤、中风、痴呆症和先天性脑畸形的研究中。这些障碍经常损害视觉处理，每一种往往都涉及运动和认知功能的严重损害。仔细调整将在本提案中制定的方案，可能会提供与这些疾病的诊断和管理相关的信息。