Comparative Vision and Attention

许多研究人员研究非人类动物是如何看待世界的。然而，考虑到动物学习和反应能力的限制，到目前为止，只有某些类型的实验是可能的。在国家科学基金会的资助下，哈佛大学和布兰迪斯大学的Nakayama博士和Pepperberg博士将通过用英语询问鸟类来解决有关灰色鹦鹉视觉处理的问题，就像询问人类受试者一样。灰鹦鹉模仿人类说话的能力是它们作为宠物广受欢迎的一个特征。佩珀伯格的灰色鹦鹉亚历克斯(现已去世)能够对简单的视觉错觉做出口头反应(例如，米勒-莱尔错觉，其中两条线在人类看来长度不同，但实际上并非如此；亚历克斯的反应与人类一样)。Nakayama博士和Pepperberg博士将训练两只鸟--格里芬和亚瑟--学习用英语语音来标记各种颜色和形状。目前的项目将研究鹦鹉是否像人一样，能够(A)完成部分被覆盖的物体的形状(例如，将一个图形识别为正方形，而不是五角形物体，即使它的一个角被圆覆盖)，这一过程正式地被称为“动态完成”和(B)“看到”实际上不是真实的物体，比如在三个以三角形方式排列的吃豆人般的部分圆圈之间“看起来”的三角形，正式地被称为“虚幻轮廓”或“Kanizsa图形”。例如，人们可能会认为鹦鹉能够推断出不能完全观察到的捕食者的存在，但还没有人能够直接问任何非人类的这样的问题。未来的研究将涉及更复杂的任务，旨在研究鸟类如何在其视觉环境中注意物体。这项研究的潜在长期目标是确定这些任务是否揭示了鸟类和人类在感知加工方面的差异。成功训练鹦鹉将使Nakayama博士和Pepperberg博士最终能够检查广泛的视觉任务，以确定哪些感知能力与鸟类和人类具有相同的潜在机制，哪些不同。这两个大脑大小非常不同的物种之间的相似之处将使我们能够理解哪些感知组件可以用较小规模的神经体系结构来实现。差异将表明哪些组件确实需要更大的大脑大小和/或复杂性。这些数据将指导未来与其他物种的比较，并为人类大脑的结构和功能提供见解，并可能为人工视觉处理器的设计提供有用的见解。

Many researchers study how nonhuman animals see the world. To date, however, only certain types of experiments have been possible, given the limitations of animal learning and response capabilities. With funding from the National Science Foundation, Drs. Nakayama and Pepperberg at Harvard and Brandeis Universities will address questions about visual processing in Grey parrots, by querying the birds in English, much as one queries human subjects. Grey parrots' ability to mimic human speech is one characteristic that has made them popular as pets. Pepperberg's Grey parrot Alex (now deceased) was able to verbally respond to simple optical illusions (e.g., the Müller-Lyer illusion, in which two lines appear to humans to vary in length but in reality do not; Alex responded as do humans). Drs. Nakayama and Pepperberg will train two birds, Griffin and Arthur, to learn to label various colors and shapes using the sounds of English speech. The current project will then examine whether parrots, like people, can (a) complete the shape of a partially covered object (e.g., recognize a figure as a square, and not as a five-cornered object, even though one of its corners is covered by a circle), a process formally known as "amodal completion" and (b) "see" objects that aren't actually real, like a triangle that "appears" between three pac-man-like partial circles that are arranged in a triangular manner, something formally known as an "illusory contour" or "Kanizsa figure". One might expect a parrot to be able, for example, to infer the presence of a predator that isn't fully observable, but no one has been able to ask any nonhuman such questions directly. Future research will involve more complex tasks designed to study how birds pay attention to objects in their visual environment.The underlying long-term goal of this research is to determine whether the tasks reveal differences in perceptual processing between birds and humans. Success in training the parrots will enable Drs. Nakayama and Pepperberg eventually to examine a broad range of visual tasks to determine which perceptual abilities share the same underlying mechanisms in birds and humans and which do not. Similarities between these two species with very different brain sizes will allow us to understand which components of perception can be implemented with smaller scale neural architecture. Differences will indicate the components that do require greater brain size and/or complexity. The data will guide future comparisons with other species and provide insights into the structure and function of the human brain and may provide useful insights for the design of artificial visual processors.