INSPIRE Proposal: Spatiotemporal structure of the rs-fMRI signal reflects contributions from different types of brain activity

该INSPIRE奖的部分资金来自社会、行为和经济科学理事会行为和认知科学部的感知、行动和认知项目，数学和物理科学理事会物理部的生命系统物理学项目，生物学理事会综合有机体系统部的神经系统集群，以及综合活动办公室。了解人类大脑如何工作的一个关键障碍是，目前不可能以非侵入性的方式检查整个大脑的活动，既要有足够的空间分辨率来解决功能区，又要有时间分辨率来解决认知过程的时间尺度。一种可能的改进是使用静息状态功能磁共振成像（rs-fMRI），它可以以可接受的分辨率对整个大脑进行无创成像。缺点是，rs-fMRI测量的是血液的相对氧合水平，除了与神经活动相关的局部贡献外，还包含非局部血流量和血容量波动的贡献。rs-fMRI信号中的特定空间和时间模式可能代表不同类型的大脑活动的可分离贡献。例如，rs-fMRI信号可能不仅携带有关神经活动的幅度和持续时间的信息，而且还携带有关神经信息处理的潜在模式或“载波”的信息。如果成功，这个项目将允许绘制整个大脑的不同类型的大脑活动，这是目前任何成像方式都无法实现的壮举。为此，研究者同时进行功能磁共振成像和直接神经记录，以确定rs-fMRI信号波动与脑电生理活动的关系，并研究rs-fMRI信号自发波动对感知和认知的影响。目标是：1)通过多模态实验和时空分析，识别高频和极低频脑电活动的rs-fMRI类似物；2)确定活动的自发波动如何影响大鼠和人类对感觉刺激的处理；3)探索高频和极低频活动的rs-fMRI类似物是否能具体预测人类在认知要求高的任务中的表现。总的来说，这些研究将使我们更好地了解在神经认知加工过程中，非侵入性测量的大脑活动的时空模式是如何结合在一起的，这些知识可能会为个体之间、个体内部、不同大脑组织（例如，损伤或疾病）的群体之间的心理加工差异提供新的见解。该奖项的一个更广泛的影响是，它将使研究人员能够加大努力，为STEM领域的母亲提供信息和资源的交流中心，帮助她们留在学术管道中。PI最近发起了一个网络资源和论坛“STEM中的妈妈”，并组织了一个女性科学家社区，致力于为该网站提供文章和信息。

This INSPIRE award is partially funded by the Perception, Action, and Cognition Program in the Division of Behavioral and Cognitive Sciences in the Directorate for Social, Behavioral, and Economic Sciences, the Physics of Living Systems Program in the Division of Physics in the Directorate for Mathematical and Physical Sciences, and the Neural Systems Cluster in the Division of Integrative Organismal Systems in the Directorate for Biology, and the Office of Integrative Activities.A key roadblock to understanding how the human brain works is that it is currently impossible to examine activity throughout the whole brain non-invasively with both a spatial resolution that is adequate to resolve functional areas and a temporal resolution on the time scale of cognitive processes. One possible improvement is to use resting state functional magnetic resonance imaging (rs-fMRI), which can image the whole brain non-invasively with potentially acceptable resolution. The drawback is that rs-fMRI measures the relative oxygenation level of the blood and contains contributions from non-localized fluctuations in blood flow and volume in addition to localized contributions linked to neural activity. The possibility exists that particular spatial and temporal patterns in the rs-fMRI signal may represent separable contributions from different types of brain activity. For example, the rs-fMRI signal may carry not only information about the magnitude and duration of neural activity but also information about the underlying patterns or "carrier waves" for neural information processing. If successful, this project would allow the mapping of different types of brain activity throughout the whole brain, a feat that cannot be achieved by any current imaging modality. To this end, the investigators conduct simultaneous functional magnetic resonance imaging and direct neural recording to determine the relation between fluctuations in the rs-fMRI signal and electrophysiological brain activity and to examine the effect of spontaneous fluctuations in the rs-fMRI signal on perception and cognition. Goals are to 1) identify rs-fMRI analogues of high frequency and very low frequency electrical activity using multimodal experiments and spatiotemporal analysis; 2) determine how spontaneous fluctuations in activity affect the processing of sensory stimuli in rats and humans; and 3) explore whether the rs-fMRI analogues of high and very low frequency activity specifically predict human performance on cognitively demanding tasks. Collectively, the studies will lead to a better understanding of how spatiotemporal patterns of brain activity measured non-invasively combine during neurocognitive processing, knowledge that is likely to provide new insights about mental processing differences across individuals, within individuals across time, and across groups with different brain organization (e.g., damage or disease).A strong broader impact of this award is that it will allow the researcher to ramp up her efforts to provide a clearinghouse for information and resources for mothers in STEM fields, helping them stay in the academic pipeline. The PI recently initiated a web resource and forum, "Moms in STEM," and has organized a community of female scientists committed to contributing articles and information to the website.