Orientation, Cognition and the Avian Brain

空间定向的研究为认知及其神经基础提供了丰富的新信息和新见解。空间定向在几乎所有动物的生活中都扮演着重要的角色，但在这项研究的三个鸟类群体中，空间定向是至关重要的：储存食物的鸟类、孵化的寄生虫和迁徙的滨鸟。储存食物的鸟类，如黑帽山雀，在秋季和冬季建立了数千个分散在空间上的食物储藏库。我之前的研究表明，山雀会记住它们的储藏室的位置，并拥有显著的海马体专门化，海马体是大脑中涉及定向和记忆的区域。储存食物的鸟类的海马体比不储存食物的鸟类的海马体大，并且表现出与食物储存相关的季节性神经发生。像褐头牛鸟一样，孵化的寄生虫在其他鸟类的巢中产卵。雌性牛鸟寻找并记住潜在寄主巢的位置，并且比雄性有更大的海马体。迁徙的滨鸟，就像半配对的琵琶一样，在加拿大北极的繁殖区和南美洲大西洋沿岸的越冬区之间飞行4000公里。这项建议介绍了在以前的发现拨款下进行的关于这些鸟类的定向、认知和大脑的研究，并提出了一项新的研究，旨在检查：1)储存食物的鸟类大脑中空间记忆的巩固，2)幼体寄生虫的空间能力和数字能力的性别差异，以及3)迁徙经历对迁徙滨鸟的两个大脑区域--海马体和N簇的影响，这是一个涉及向地球磁场定向的区域。这项研究将促进我们对定向的基本大脑机制的理解，结果适用于动物和人类，将为动物的认知过程提供新的见解，并将导致对加拿大本土鸟类行为的更多理解和欣赏。

Research on spatial orientation has provided a wealth of new information and insights into cognition and its neural basis. Spatial orientation plays an important role in the lives of nearly all animals but is critical in the three groups of birds that are the focus of this research: food-storing birds, brood parasites and migratory shorebirds. Food-storing birds, like black-capped chickadees, establish thousands of spatially-dispersed food caches during the fall and winter. My previous research has shown that chickadees remember the locations of their caches and possess remarkable specialization of the hippocampus, a brain region involved in orientation and memory. The hippocampus of food-storing birds is larger than the hippocampus of non-storing birds and exhibits seasonal neurogenesis associated with food storing. Brood parasites, like brown-headed cowbirds, lay their eggs in the nests of other birds. Female cowbirds search for and remember the locations of potential host nests and have a larger hippocampus than males. Migratory shorebirds, like semipalmated sandpipers, fly 4000 km between their breeding areas in the Canadian arctic and wintering areas on the Atlantic coast of South America. This proposal describes research conducted under the previous Discovery grant on orientation, cognition and the brain of these birds and proposes new research examining: 1) Consolidation of spatial memory in the brain of food-storing birds, 2) Sex differences in spatial ability and numerical competence in brood parasites, and 3) The effect of migratory experience on two brain regions of migratory shorebirds, the hippocampus and Cluster N, a region involved in orientation to the earth's magnetic field. This research will advance our understanding of the fundamental brain mechanisms of orientation with results applicable to both animals and humans, will provide new insights into the cognitive processes of animals, and will lead to greater understanding and appreciation of the behaviour of native Canadian birds.