This project dovetails with a major research project at the University of Bielefeld, Germany, that uses wooden construction pieces in the development of machine recognition systems for language and vision. Our previous work has demonstrated unexpected trade-offs between observer eye and head movements and the use of visual memory in ongoing tasks. Understanding the operation of visual memory is crucial in making the transition from an understanding of low-level perceptual machinery to an understanding of how perception mediates ongoing sensori-motor bahavior. The aim of this project is to develope a new paradigm for exploring simple sensori-motor behaviors, in which observers construct wooden models of objects. This paradigm is much richer than our earlier paradigm in the kinds of behavior we can observe. For example, we can observe the perceptual learning process that leads to more efficient perceptual encoding.