Revealing functional networks and circuits of the posteromedial cortex withanatomical connectivity

项目摘要 后内侧皮层是一个在许多精神疾病中特别异常的大脑区域， 包括抑郁精神分裂和焦虑然而，传统上很少受到关注， 神经科学家，部分原因是我们不了解其潜在的生物学。我们建议对此作出补救 通过在非人类灵长类动物中使用束追踪和扩散来揭示后内侧皮质回路的问题- 非人类灵长类动物和人类的加权磁共振成像。这条管道将使我们能够创造 后内侧皮质根据其解剖学连接性的分割。首先，我们建议 非人类灵长类动物的后内侧皮质，这将使我们能够分析其 与其他更好理解的大脑区域的连接。我们将使用这些数据分割后内侧 根据其解剖学连接性。我们希望不同的部分将连接到不同的， 大脑中定义明确的网络。接下来，我们将收集非人类的弥散加权神经成像数据， 灵长类动物和人类。虽然这种方法允许非侵入性地检测一些连接，但它是高度复杂的。 容易出错。我们将使用在追踪数据中识别的白色物质组织的原理 来引导和调试这些神经成像数据。因为神经束追踪不能在人类身上进行， 管道提供了一种罕见的可能性来推断人脑中的解剖连接。最后，基于先验 在神经成像实验中，科学家们假设后内侧皮层可能与一个神经元连接。 特别是大量的大脑区域和网络。因此，我们想确定轴突的范围 这个大脑区域的神经元的侧支化。换句话说，一个后内侧皮层神经元 投射到许多其他的大脑区域，还是这些回路在很大程度上是独立的？我们共同期待这些项目 将阐明PMC解剖连接的方式，大规模的神经影像网络可以连接 特定的神经回路。

Project Summary The posteromedial cortex is a brain region that is especially abnormal in many psychiatric diseases, including depression, schizophrenia, and anxiety. However, it has traditionally received little attention from neuroscientists, in part because we do not understand its underlying biology. We propose to remedy this problem by uncovering posteromedial cortical circuits using tract-tracing in nonhuman primates and diffusion- weighted magnetic resonance imaging in nonhuman primates and humans. This pipeline will allow us to create a segmentation of the posteromedial cortex according to its anatomical connectivity. First, we propose to tile the nonhuman primate posteromedial cortex with tract-tracer injections, which will allow us to analyze its connectivity with other, better-understood brain regions. We will use these data to segment the posteromedial cortex according to its anatomical connectivity. We expect that different segments will connect with distinct, well-defined networks within the brain. Next, we will collect diffusion-weighted neuroimaging data in nonhuman primates and humans. Although this method allows noninvasive detection of some connections, it is highly susceptible to errors. We will use the principles of white matter organization identified in the tract-tracing data to guide and debug these neuroimaging data. Because tract-tracing cannot be performed in humans, this pipeline offers a rare possibility to infer anatomical connectivity in the human brain. Finally, based on prior neuroimaging experiments, scientists have hypothesized that the posteromedial cortex may connect with a particularly large number of brain regions and networks. Thus, we would like to determine the extent of axonal collateralization in the neurons of this brain region. In other words, does a single posteromedial cortical neuron project to many other brain regions, or are the circuits largely separate? Together, we expect these projects will elucidate PMC anatomical connectivity in such a way that large-scale neuroimaging networks can be linked with specific neuronal circuits.