CRCNS: Processing speed in the human connectome across the lifespan

人脑中的通路形成了一个支持大脑功能的大型网络。这种连接体的结构在整个生命周期中都会发生变化，众所周知，白质通路从童年发展到老年。然而，人们还不太清楚这些变化是如何影响这些通路上的功能性交流的，这些通路在毫秒的时间尺度上处理信息。研究人脑功能连接的这些时间特性的一种独特方法是通过单脉冲电刺激颅内电极，在那里脉冲沿着皮质网络传播，可以研究其方向性和传输速度。然而，在癫痫治疗中，这些颅内电极是出于临床目的而放置的，导致不同患者的位置有相当大的差异。为了能够对特定的网络进行全面的研究，我们需要找到一种方法，将多个受试者的颅内神经生理数据合并到一个单一的坐标空间，并将其合并到一个专用的结构化数据库中。这个合作项目将组织一个大型数据库，其中包括现有的和新获得的单脉冲脑电刺激的颅内脑电(IEEG)数据。通过社区的努力，iEEG数据的标准结构正在开发：iEEG对大脑成像数据结构的扩展(iEEG-BIDS)。神经成像数据将与iEEG数据一起存储在BIDS结构中，以绘制每个电极的解剖位置，这样就可以很容易地识别电极在同一网络上的受试者。所有投标元数据都是人类和机器可读的，允许使用覆盖同一网络的电极轻松提取主题。BIDS应用程序将被开发来从刺激诱发的反应中确定跨网络的速度和方向性，使我们能够评估跨人类连接体的前馈和反馈处理的时间属性的年龄相关变化，包括涉及许多认知功能和精神疾病的路径。该项目将增加对人类一生中沿着连接体传播的速度和方向性的独特洞察力，这对于建立人类大脑功能的网络模型和开发新的治疗性脑刺激技术是必要的，该技术可以调节涉及金属疾病的网络。

The pathways in the human brain form a large network that supports brain function. The structure of this connectome changes across the life span, and it is well known that white matter pathways develop from childhood to old age. It is, however, less well understood how these changes influence the functional communication across these pathways, which processes information on the timescale of milliseconds. A unique way of studying these temporal properties of functional connectivity in the human brain is through single pulse, electrical stimulation of intracranial electrodes, where pulses spread along cortical networks and the directionality and transmission speed can be studied. However, these intracranial electrodes are placed for clinical purposes in epilepsy treatment, resulting in quite some variation in locations across patients. To enable comprehensive research on specific networks, we need to find a way of consolidating multi-subject intracranial neurophysiological data into a single coordinate space, and combine this in a dedicated and structured database. This collaborative project will organize a large database of existing and newly acquired intracranial electroencephalography (iEEG) data with single pulse electrical brain stimulation. Through a community effort, a standard structure for iEEG data is being developed: the iEEG extension to the Brain Imaging Data Structure (iEEG-BIDS). Neuroimaging data will be stored in the BIDS structure alongside iEEG data to map the anatomical location of every electrode, such that subjects with electrodes on the same network can be easily identified. All BIDS metadata are both human and machine readable, allowing the easy extraction of subjects with electrodes covering the same network. BIDS apps will be developed to determine the speed and directionality across networks from the stimulation-evoked responses, allowing us to assess age related changes in the temporal properties of feedforward and feedback processing across the human connectome, including the pathways involved in many cognitive functions and psychiatric illnesses. This project will add unique insight into the speed and directionality of transmission along the human connectome across the life span, which is necessary to build network models of human brain function and develop novel therapeutic brain stimulation technologies that modulate the networks involved in metal illnesses.