This dissertation investigates how figurative uses of motion verbs are understood in sentences such as 'The highway runs through the valley', and 'The mountain range goes from Canada to Mexico'. These sentences feature a motion verb ('run', 'go'), but do not explicitly express motion through physical space. According to many cognitive linguists, such sentences involve 'fictive motion', an implicit, simulated motion that proceeds from one point to another along the trajectory that is expressed by the subject noun phrase (e.g., highway). Six experiments investigated the possibility that simulated motion occurs in the on-line understanding of fictive motion sentences. In each experiment, participants read a story about a protagonist traveling through physical space, and then made a decision about whether a fictive motion target sentence related to the story. In all experiments, decision times were longer for the fictive motion targets (e.g., 'A road crosses the desert') after stories in which travel involved a slow rate, far distance, or cluttered terrain than they were after stories in which travel involved a fast rate, a short-distance, or a clutter-free terrain. The results suggest that (a) participants construct a spatial model of the scene they read about, (b) re-activate or simulate motion to make a decision about the fictive motion target, and (c) such simulated motion mirrors actual motion in many ways. (Teenie Matlock)