The sensory and cognitive basis of three-dimensional distance estimation in a teleost fish - WCUB, ENWW

研究摘要：动物导航，或者更具体地说，动物如何学习、记忆和使用来自其空间环境的信息的问题，在过去的50年里受到了越来越多的关注，2014年诺贝尔奖的获得者是因为发现了负责编码哺乳动物海马体和内嗅觉皮质空间的脑细胞1，2。归巢导航，即在觅食、追逐配偶或躲避捕食者的旅程后返回目标的能力，可能是研究最广泛的导航形式，证据表明它在脊椎动物和无脊椎动物分支中的广泛重要性。在这里，我们将它与真正的导航分开，真正的导航是指即使在实验移位后也能回家的能力(鸟3；龟4)。为简单起见，归巢可分为三大部分：踪迹追踪，例如跟随在外出旅程中沉积的信息素踪迹；在已学习的视觉地标之间导航；以及路径整合。后者包括动物独立于视觉地标不断更新其从原点(巢穴)的距离和方向，这样它就可以跟随一个直接的载体回家，而不管组成向外旅程的一系列载体5-7。为了整合路径，动物需要能够持续跟踪其移动的距离和方向。前一项指标将是本项目的重点；使用墨西哥洞穴鱼作为我的模型系统，我的目标是使用一个已经在试点研究中预先测试的简单行为任务，来探索硬骨鱼在三维空间中距离估计的感觉和认知基础。与路径整合所需的方向分量不同，到目前为止还没有关于鱼类距离估计的准确性或机制的实证研究。因此，该项目有两个核心主题：(I)FISH能否估计距离，如果能，准确度如何？(Ii)他们使用什么感官信息来估计距离？中上层鱼类是研究空间认知的有趣的实验对象，因为它们必须在体积空间中导航，从水平和垂直平面提取并编码相关的感觉信息。这为研究直角平面上里程计的感觉和认知基础之间的任何差异提供了额外的范围。与老鼠等表面绑定的动物不同，它们在行为和神经水平上表现出各向异性的空间表征，而垂直编码的精确度较低，自由移动的鱼可能更有可能表现出空间的各向同性表征，在两个平面上都具有相同的精度，就像最近在蜂鸟8、9和批次10、11中在神经层面上发现的那样，这两种动物也都自由地利用体积空间。BBSRC优先领域：该项目符合跨学科生物科学DTP中的动植物生物学综合主题

Research Summary:Animal navigation, or more specifically the problem of how animals learn, remember and use information from their spatial environment, has received increasing interest particularly over the last fifty years, with the 2014 Nobel Prize awarded for the discovery of brain cells responsible for encoding space in the hippocampus and entorhinal cortex of mammals1,2. Homing navigation, the ability to return to a goal following a foraging journey, pursuit of a mate or predator avoidance for example, is perhaps the most broadly studied form of navigation, with evidence of its widespread importance across the vertebrate and invertebrate clades. Here, we are separating it from 'true navigation', the ability to return home even after experimental displacement (birds3; turtles4). For simplicity, homing can be split into three broad strands: trail following, such as following a pheromone trail deposited on the outward journey; piloting between learned visual landmarks; and, path integration. The latter involves the animal continuously updating its distance and direction from its origin (home nest) independently of visual landmarks, such that it can follow a direct vector home regardless of the series of vectors making up the outward journey5-7. In order to path integrate, an animal needs to be able to continuously keep track of the distance and direction of its travel. The former metric will be the focus of this project; using the Mexican cavefish Astyanax fasciatus as my model system, I aim to use a simple behavioural task that has been pre-tested in a pilot study, to exploreboth the sensory and cognitive basis of distance estimation in teleost fish across three-dimensional space. Unlike the directional component required for path integration, there have thus far been no empirical studies investigating the accuracy or mechanisms of distance estimation in fish. The project therefore has two core themes: (i) Can fish estimate distance, and if so with what accuracy? (ii) What sensory information do they use to estimate distance? Pelagic fish are interesting experimental subjects for the study of spatial cognition because they must navigate through volumetric space, extracting and encoding relevant sensory information from both the horizontal and vertical planes. This provides additional scope for investigating any differences between the sensory and cognitive basis of odometry across the orthogonal planes. Unlike surface bound animals, such as rats, that show anisotropic representation of space at behavioural and neural levels with lower accuracy vertical encoding, freely moving fish are perhaps more likely to show isotropic representation of space, with equal accuracy in both planes, as has recently been found inhummingbirds8,9 and at the neural level in bats10,11, both of which also freely exploit volumetric space. BBSRC Priority Area: This project fits into the integrative animal and plant biology theme in the Interdisciplinary Bioscience DTP