Seeing the world in a different light - discovering how vertebrates see polarized light

从不同的角度看世界 - 发现脊椎动物如何看到偏振光

• 批准号: BB/H01635X/1
• 负责人: Nicholas Roberts
• 金额: $ 41.43万
• 依托单位: University of Bristol
• 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=BB%2FH01635X%2F1
• 关键词: Seeing; world; different; light; discovering

Most animals see the world in a very different way from us and differ in their ability to see detail, movement and colour. This study will investigate an aspect of vision beyond these familiar visual properties, and one that is totally alien to us: the ability to see polarized light. Polarization describes the direction in which a wave of light oscillates and, although humans are unaware of this, light around us is polarized. Polarization vision is often considered a characteristic of invertebrates such as insects, but many vertebrates can also detect and decode the polarization of light. This gives them extra visual information for tasks such as object recognition, communication and camouflage detection. It also adds an extra dimension to other sensory abilities, such as smell or magnetoreception for use in navigation and has potential to enhance contrasts in environments where light is scattered, particularly underwater. In this proposed research, we will investigate polarization vision in vertebrates, using fish as model organisms. Several species of fish have been shown relay information about the polarization of light from the eye to the brain. However, very little is known about either the way the eye detects the polarization of light, or how fish use it in their behaviour. Our experiments build on the work of the PI who recently, and for the first time, showed that when particular types of light sensitive cells in vertebrate retina (called cones) were illuminated end on, as they are in the eye, they absorb differently-orientated linear polarized light to different degrees. Our measurements will be made by microspectrophotometry and microspectropolarimetry - techniques that measure how polarized light is absorbed and transmitted through microscopic-sized samples. We will use two techniques for microspectrophotometry: (i) using a conventional instrument in which single cells are measured in a side-on orientation to validate data from (ii) an innovative and specifically constructed 2-dimensional imaging instrument that will allow the simultaneous measurement of many cells in a retina. Along with novel microspectropolarimetric measurements, made by adapting the 2-D microspectrophotometer, we will determine how species known to have different retinal anatomies (e.g. square or linear arrangements of cones in their retinas) and different complements of cone photoreceptor types (e.g. those with and without UV-sensitive cones) absorb polarized light. We will ally these spectral measurements with electron microscopy studies to quantify the organization of proteins and lipids in cone cell outer segments which we suggest may well be the mechanism that enables individual photoreceptors to be sensitive to differently polarized light. The part of cones that absorb light have already been shown to have unexplained organizational sub-structure, but the significance of such structures for photoreceptor function has yet to be demonstrated. Finally, we will use behavioural tests to screen various species of fish for behavioural demonstration of polarization vision, this being the important end point of any sensory capability. Fish readily learn visual tasks that result in a reward such as food and we will use this attribute to test for polarization sensitivity. By using a novel method based on apparatus incorporating nematic liquid crystal cells to control the polarization of the stimulus that the fish see in the experiments, we will investigate their ability to discriminate horizontal from vertical polarization; the importance of ultraviolet light in polarization vision; and the frequency, or speed, with which changes in polarization can be seen. Ultimately this research will answer one of the most significant unanswered questions in vision biology: How do vertebrates see polarized light?

大多数动物看世界的方式与我们非常不同，它们对细节、运动和颜色的观察能力也不同。这项研究将研究视觉的一个方面，超越这些熟悉的视觉特性，一个是完全陌生的我们：看到偏振光的能力。偏振描述了光波振荡的方向，尽管人类没有意识到这一点，但我们周围的光是偏振的。偏振视觉通常被认为是昆虫等无脊椎动物的特征，但许多脊椎动物也可以检测和解码光的偏振。这为它们提供了额外的视觉信息，用于物体识别，通信和伪装检测等任务。它还为其他感官能力增加了一个额外的维度，例如用于导航的嗅觉或磁感受，并有可能在光线散射的环境中增强对比度，特别是在水下。在这项拟议的研究中，我们将调查偏振视觉脊椎动物，使用鱼类作为模式生物。有几种鱼被证明可以将光的偏振信息从眼睛传递到大脑。然而，人们对眼睛检测光的偏振的方式以及鱼类如何在其行为中使用它知之甚少。我们的实验建立在PI的工作基础上，PI最近首次表明，当脊椎动物视网膜中特定类型的光敏细胞（称为视锥细胞）被照亮时，就像它们在眼睛中一样，它们吸收不同方向的线性偏振光到不同程度。我们的测量将通过显微分光光度法和显微偏振光谱法进行-这些技术测量偏振光如何被吸收和透射通过显微尺寸的样品。我们将使用两种技术进行显微分光光度法：（i）使用传统仪器，其中单细胞在侧面测量，以验证来自（ii）创新和专门构建的二维成像仪器的数据，该仪器将允许同时测量视网膜中的许多细胞。沿着通过调整2-D显微分光光度计进行的新颖的显微分光偏振测量，我们将确定已知具有不同视网膜解剖结构（例如，视网膜中锥体的正方形或线性排列）和锥体感光器类型的不同补充（例如，具有和不具有UV敏感锥体的那些）的物种如何吸收偏振光。我们将联合这些光谱测量与电子显微镜研究，以量化的蛋白质和脂质的组织在锥细胞外节，我们建议很可能是机制，使个人感光细胞敏感的不同偏振光。吸收光的视锥细胞部分已经被证明具有无法解释的组织亚结构，但这种结构对感光器功能的重要性尚未得到证实。最后，我们将使用行为测试来筛选各种鱼类，以展示偏振视觉的行为，这是任何感官能力的重要终点。鱼很容易学习视觉任务，导致奖励，如食物，我们将使用这个属性来测试偏振敏感性。通过使用一种新的方法的基础上的设备，将液晶电池控制的刺激，鱼在实验中看到的偏振，我们将调查他们的能力，以区分水平从垂直偏振;紫外线在偏振视觉的重要性;和频率，或速度，可以看到偏振的变化。最终，这项研究将回答视觉生物学中最重要的未回答的问题之一：脊椎动物如何看到偏振光？

项目成果

Animal Polarization Imaging and Implications for Optical Processing

• DOI: 10.1109/jproc.2014.2341692
• 发表时间: 2014-08
• 期刊: Proceedings of the IEEE
• 影响因子: 20.6
• 作者: Nicholas Roberts;M. How;M. Porter;S. Temple;R. Caldwell;Samuel B. Powell;V. Gruev;N. Marshall;T. Cronin

Disordered animal multilayer reflectors and the localization of light.

• DOI: 10.1098/rsif.2014.0948
• 发表时间: 2014-12-06
• 期刊: Journal of the Royal Society, Interface
• 作者: Jordan TM;Partridge JC;Roberts NW
• 通讯作者: Roberts NW

Polarisation vision: overcoming challenges of working with a property of light we barely see.

• DOI: 10.1007/s00114-018-1551-3
• 发表时间: 2018-03-27
• 期刊: Die Naturwissenschaften
• 作者: Foster JJ;Temple SE;How MJ;Daly IM;Sharkey CR;Wilby D;Roberts NW
• 通讯作者: Roberts NW

Non-polarizing broadband multilayer reflectors in fish.

• DOI: 10.1038/nphoton.2012.260
• 发表时间: 2012-11
• 期刊: Nature photonics
• 影响因子: 35

Perceiving polarization with the naked eye: characterization of human polarization sensitivity.

• DOI: 10.1098/rspb.2015.0338
• 发表时间: 2015-07-22
• 期刊: Proceedings. Biological sciences
• 作者: Temple SE;McGregor JE;Miles C;Graham L;Miller J;Buck J;Scott-Samuel NE;Roberts NW
• 通讯作者: Roberts NW