Functional MRI in Schizophrenia

项目总结/摘要 海马体（HPC）是脑的一个区域，其广泛涉及脑缺血的病理生理学。 精神分裂症（SZ）。SZ的功能连接模型表明，干扰也存在于功能连接中。 HPC和其他多个大脑区域和网络之间的连接。异常HPC静息状态 功能连接（rsFC）已经被报道与多个大脑区域和网络，但还没有 与文献一致。这种不一致主要是由于BOLD的固有局限性造成的， 基于rsFC技术在大的敏感区域，如HPC。由于这种限制，HPC（以及其他 易感区域）通常基本上被排除在对全脑rsFC分析的贡献之外。的 异常HPC rsFC结果的不一致不仅严重妨碍了我们对 HPC在SZ神经病理学中的作用，但也明显限制了各种初步研究结果的推广。 小样本量的研究，并可能最终阻碍SZ诊断的潜在生物标志物的验证 和治疗。 在这项概念验证研究中，我们提出了一种单激发单标记背景抑制动态动脉 自旋标记（sbDASL）技术研究rsFC与HPC，这两个重要性，阐明其作用， SZ的病理生理学，但也因为它提供了一个理想的情况下，以验证这种新的成像技术 更广泛地检查FC与其他区域和全脑分析。所提出的sbDASL技术 克服了现有技术在SZ研究rsFC中的几个当前局限性。最重要的是， 提高了现有基于DASL的HPC稳健评估方法的空间和时间分辨率 rsFC。 在该提案中，我们将寻求发展sbDASL技术，并证明其在检测HPC方面的优越性 rsFC前扣带皮层（ACC）和后扣带皮层（PCC）在健康受试者中的作用，以及其改善 与BOLD技术相比，基线的重现性和对急性咖啡因挑战的敏感性。我们将 比较HPC rsFC与ACC和PCC在无抗精神病药物的SZ患者中的效应量，相对于 匹配的健康对照，使用sbDASL和BOLD。我们将进一步探索sbDASL的功能， BOLD，在区分SZ患者和健康对照之间使用跨多个大脑的rsFC测量 网络.

Project Summary/Abstract The hippocampus (HPC) is one area of the brain that is broadly implicated in the pathophysiology of schizophrenia (SZ). Functional connectivity models of SZ suggest that disturbances also exist in the functional connections between the HPC and multiple other brain regions and networks. Aberrant HPC resting-state functional connectivity (rsFC) has been reported with multiple brain regions and networks, but has not yet been consistent across the literature. Such inconsistency is mainly caused by the inherent limitation of the BOLD- based rsFC techniques in large susceptibility regions like HPC. Due to this limitation, HPC (as well as other susceptible regions) is often essentially excluded from contributing to whole-brain rsFC analyses. The inconsistency of findings for abnormal HPC rsFC not only severely hampers our understanding of the role of HPC in SZ neuropathology, but also markedly constrains the generalization of findings from various preliminary studies with small sample sizes, and may ultimately stunt the validation of potential biomarkers for SZ diagnosis and treatment. In this proof-of-concept study, we propose a single-shot single-label background-suppressed dynamic arterial spin labeling (sbDASL) technique to study rsFC with the HPC, both for the importance of elucidating its role in the pathophysiology of SZ, but also because it provides an ideal case to validate this novel imaging technique more broadly to examine FC with other areas and for whole brain analyses. The proposed sbDASL technique overcomes several current limitations of existing techniques in the study of rsFC in SZ. Most importantly, sbDASL improves the spatial and temporal resolution of existing DASL-based approaches for robust assessment of HPC rsFC. In the proposal, we will seek to develop the sbDASL technique and demonstrate its superiority in detecting HPC rsFC anterior cingulate cortex (ACC) and posterior cingulate cortex (PCC) in healthy subjects, and its improved reproducibility at baseline and sensitivity to acute caffeine challenge, compared to the BOLD technique. We will compare the effect sizes of the HPC rsFC with ACC and PCC in antipsychotic-free patients with SZ, relative to matched healthy controls, using sbDASL and BOLD. We will further explore the capability of sbDASL, compared to BOLD, in differentiating between SZ patients and healthy controls using rsFC measures across multiple brain networks.