In a fraction of a second-in a single glance-we comprehend complex scenes never encountered previously. What is the basis of this extraordinary capacity? A prominent theory of shape recognition holds that objects exist in memory as an arrangement of simple, regular, 2D and 3D geometrical shapes, such as bricks, cones, cylinders, wedges, circles, and squares. To see a novel scene is to make contact with these pre-prepared elementary shapes in memory, called geons. How does this extraordinary capacity arise? By one hypothesis, a rich early experience with natural extended contours would be sufficient. An alternative hypothesis is that geons derives from our early experience immersed in the geometry of a manufactured world. Would individuals from a culture with only minimal exposure to manufactured-world artifacts show the same kinds of perception as artifact-immersed college students? Would they, instead, have greater sensitivity for distinguishing among highly irregular shapes, such as bushes, clouds, or mountain ridges? Dr. Biederman and Marissa Nederhouser, M.A., will answer the latter questions in an investigation of shape discrimination by the Himba. The Himba are a semi-nomadic tribe in northern Namibia with minimal exposure to Western artifacts and a language that contains none of the terms for simple shapes (such as those listed for some of the geons). Ms. Nederhouser will be joining a British team studying color and linguistic discriminations. There is some urgency in this research because the Namibian government will soon expand tourism to this remote area, with the consequent increase of exposure to manufactured-world artifacts. Broader impacts of this research include a better understanding of natural diversity in a fundamental mental capability.
