Orientation, Cognition and the Avian Brain

空间定向的研究为认知及其神经基础的研究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起着重要的作用，但在本研究的三种鸟类中起着至关重要的作用：食物储存鸟、幼虫寄生物和迁徙滨鸟。储存食物的鸟类，如黑冠山雀，在秋季和冬季建立了数千个空间分散的食物贮藏点。我之前的研究表明，山雀能记住它们藏物的位置，并且拥有显著的海马区，这是一个与方向和记忆有关的大脑区域。储存食物的鸟的海马比不储存食物的鸟的海马大，并表现出与储存食物有关的季节性神经发生。寄生幼虫，如褐头牛鹂，在其他鸟类的巢中产卵。雌性牛郎鸟寻找并记住潜在寄主巢穴的位置，它们的海马体比雄性大。迁徙的滨鸟，如半舌鹬，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。该提案描述了在先前的发现基金下对这些鸟类的定向、认知和大脑进行的研究，并提出了新的研究：1)储食鸟大脑空间记忆的巩固；2)寄生物幼虫空间能力和数值能力的性别差异；3)迁徙经历对迁徙滨鸟海马和簇N（一个与地球磁场方向有关的区域）的影响。这项研究将促进我们对基本的大脑定向机制的理解，其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，并将使我们更好地理解和欣赏加拿大本土鸟类的行为。

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.