The neurophysiological basis of prolonged negative BOLD signals

长时间负 BOLD 信号的神经生理学基础

• 批准号: G1002194/1
• 负责人: Jason Berwick
• 金额: $ 71.08万
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2011
• 资助国家: 英国
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=G1002194%2F1
• 关键词: neurophysiological; basis; prolonged; negative; BOLD

A technique called blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) can determine levels of different activity in parts of the living human brain and how malfunctions can occur in disease. However, this technique relies on changes in local blood oxygenation rather than measuring the electrical activity in the brain directly. How increases in brain activity results in blood changes has started to be understood, but how and if decreases in activity affect brain blood oxygen is not at all characterised making neuroimaging data very difficult to interpret in terms of decreases in brain activity. Despite this uncertainty, scientists are stating to use FMRI to infer decreases in brain activity and if this inference is correct their studies suggest that the majority of psychiatric (e.g. schizophrenia, major depressive disorder), neuro-developmental (e.g. Autism) neurological (e.g. Alzheimer?s) brain diseases are characterised an inability to ?turn-off? rather ?turn-on? specific brain regions during mental tasks. By directly measuring reductions brain activity, neuroimaging signals and blood oxygen content at the same time we hope to understand the relationships between them and allow this vital aspect of neuroimaging to further our understanding of brain function and its malfunction in disease states.

一种称为血氧水平依赖（BOLD）功能磁共振成像（fMRI）的技术可以确定活人大脑部分不同活动的水平，以及疾病中出现故障的原因。然而，这项技术依赖于局部血液氧合的变化，而不是直接测量大脑中的电活动。大脑活动的增加如何导致血液变化已经开始被理解，但是大脑活动的减少如何以及是否会影响脑血氧却完全没有特征，这使得神经成像数据很难根据大脑活动的减少来解释。尽管存在这种不确定性，科学家们仍声称使用功能磁共振成像来推断大脑活动的减少，如果这一推断是正确的，他们的研究表明，大多数精神疾病（如精神分裂症、重度抑郁症）、神经发育疾病（如自闭症）、神经疾病(如阿尔茨海默病？S)脑部疾病的特征是无法关闭？而刺激?在脑力任务中特定的大脑区域。通过直接测量脑活动减少，同时神经成像信号和血氧含量，我们希望了解它们之间的关系，并允许神经成像的这一重要方面进一步了解大脑功能及其在疾病状态下的功能障碍。