Comparative cognition of spatial orientation

所有可移动的物种都必须定位，然而我们对这个过程是如何实现的知之甚少。我的总体目标是研究动物在它们的环境中如何定位。空间信息可以分为特征和几何。特征是物体（如树木或岩石）；而几何学是物体或表面之间的度量关系（例如，距离或方向）。对这些线索的相对依赖可能受到发育的影响。一个可验证的假设是，随着成熟，线索编码从本地线索转移到包括更远的线索。为了验证这一假设，我将在我的实验室里饲养鸟类，并通过系统地改变它们的环境的测试，研究空间线索的使用如何随着发展而变化。生态压力也可能影响空间线索的使用方式。在这种情况下，可测试的假设是，依赖空间记忆生存的动物会编码稳定的线索，这些线索对环境变化很强大，比如几何形状，而短期依赖空间记忆的动物会使用非常独特但不那么稳定的线索，比如特征。为了验证这一假设，我将调查三种相关鸟类的空间线索使用情况。其中两种是储存食物的鸟类，它们在不同程度上依赖于储存食物的能力，而第三种根本不储存食物。通过研究这些鸟类如何使用空间线索，我可以确定食物储存的生态压力是否影响了哪些空间线索被编码。最后，鸟类提供了一个独特的机会来研究每个大脑半球是如何编码空间线索的。鸟类缺乏胼胝体，而胼胝体是人类大脑半球间连接的主要来源。这就导致了类似于“自然分裂”的情况；进入右眼的视觉信息由左脑半球处理，而左眼则相反。使用一种非侵入性的眼罩技术，我将研究每个半球如何独立工作，以及两个半球如何一起工作来编码空间线索。我的研究项目的新颖性将把空间认知领域带向新的方向，并对基础科学、临床神经心理学和神经科学产生影响。

All mobile species must orient, yet we know surprisingly little about how this process is achieved. My general objective is to study how animals orient within their environments. Spatial information can be classified as features or geometry. Features are objects (e.g., trees or rocks); whereas geometry is the metric relationship between objects or surfaces, (e.g., distances or directions). The relative reliance on these cues may be influenced by development. One testable hypothesis is that with maturity, cue encoding shifts from local cues to include more distant cues. To examine this hypothesis, I will rear birds in my laboratory and through tests which systematically alter their environment, examine how spatial cue use changes with development. Ecological pressures may also influence how spatial cues are used. In this case, the testable hypothesis is that animals which rely on their spatial memories for survival will encode stable cues that are robust to environmental change - i.e., geometry, whereas animals which rely on their spatial memory for short time periods will use cues that are very distinctive but not as stable - i.e., features. To test this hypothesis, I will investigate spatial cue use in three species of related birds. Two of these species are food-storing birds, each relying on their ability to store food to differing degrees, whereas the third species does not store food at all. By examining how these birds use spatial cues I can determine whether the ecological pressure of food-storing influences which spatial cues are encoded. Finally, birds allow for a unique opportunity to examine how each brain hemisphere encodes spatial cues. Birds lack a corpus callosum, the major source of interhemispheric connections in humans. This results in a "natural split-brain" like situation; visual information coming into the right eye is processed by the left hemisphere and vice versa for the left eye. Using a non-invasive eye capping technique, I will investigate how each hemisphere works independently, as well as how the two hemispheres work together to encode spatial cues. The novelty of my research program will take the field of spatial cognition in new directions, with implications for basic science, clinical neuropsychology and neuroscience.