Optical Detection of Neural Activity

神经活动的光学检测

• 批准号: 7139440
• 负责人: TANER AKKIN
• 金额: $ 27.65万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-15 至 2008-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7139440
• 关键词: action potentials; axon; calcium; experimental designs; fasting; light intensity; light scattering; literature survey; measurement; motivation; olfactory nerve; optical tomography; osmotic pressure; role; squid

DESCRIPTION (provided by applicant): Transient structural changes during neural activity are directly related to the action potential propagation. The first non-contact optical measurement of these fast (approximately 1 millisecond) and small (approximately 1 nanometer) changes (Akkin, 2003; Akkin et al., 2004) has been recently reported by using differential phase contrast optical coherence tomography (DPC-OCT) [1,2]. The measurements are depth-resolved and do not require exogenous chemicals or reflection coatings. The method, highlighted as of special interest in a review article [3], is innovative and is expected to have a major impact in neuroscience. The long term objective is to elucidate the origin of the transient structural changes and its contributions to the optical indications of neural activity. The hypothesis behind the work is that the transient structural changes in the active nerve, despite its small magnitude, is a major contributor to many optical signals indicating the neural activity. The hypothesis is derived from the following observations: (i) 1 nm swelling is approximately 1,800 times greater than the retardation change (AR) reported for a squid giant axon. The retardation is the product of birefringence (an optical property) and thickness, (ii) The non-contact measurements revealed nanometer scale swelling and shrinkage. Similarly, positive and negative changes in retardation and light scattering have been reported for different preparations that are both potentially related to the transient thickness change. Based on these observations, the specific aims of our proposed research are designed to correlate the transient structural changes and the optical signals indicating the neural activity.

描述（由申请人提供）： 神经活动期间的瞬时结构变化与动作电位传播直接相关。最近，通过使用微分相对比光学相干断层扫描（DPC-OCT），已报道了这些快速（约1毫秒）和小（大约1纳米）变化（大约1毫秒）和小（大约1纳米）变化的第一个非接触式光学测量（Akkin，2003； Akkin等，2004）[1,2]。测量是深度分辨的，不需要外源化学物质或反射涂层。该方法在评论文章[3]中特别关注的方法是创新的，预计将对神经科学产生重大影响。长期目标是阐明瞬态结构变化的起源及其对神经活动的光学指示的贡献。工作背后的假设是，尽管有幅度很小，但活性神经的瞬时结构变化是许多指示神经活动的光学信号的主要贡献者。该假设来自以下观察结果：（i）1 nm肿胀比报道的鱿鱼巨型轴突报道的延迟变化（AR）大约大约1,800倍。延迟是双折射（光学特性）和厚度的产物，（ii）非接触式测量结果表明纳米尺度膨胀和收缩。同样，已经报道了与瞬态厚度变化有关的不同制剂的延迟和光散射的正变化。基于这些观察结果，我们提出的研究的具体目的旨在将瞬态结构变化和指示神经活动的光学信号相关联。