Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Brain and Cognitive Sciences, 2007.Includes bibliographical references (p. 118-130).Perceptual systems are specialized for transducing and interpreting information from the environment. But perceptual systems can also be used for processing information that arises from other sources, such as mental imagery and cued associations. Here we ask how a particular sensory property, visual motion, is represented when it is not directly perceived but only imagined or inferred from other cues. In a series of experiments, a motion adaptation paradigm is used to assess directional properties of the responses to mental imagery of motion and viewing photographs that depict motion. The results show that both imagining motion and inferring motion from pictures can cause direction-specific adaptation of perceptual motion mechanisms, thus producing a motion aftereffect when a subsequent real motion stimulus is viewed. The transfer of adaptation from implied and imagined motion to real motion indicates that shared mechanisms are used for the perception, inference and imagination of visual motion.by Jonathan Winawer.Ph.D.