The Kappa effect or perceptual time dilation is a form of temporal illusion verifiable by experiment. The temporal duration between a sequence of consecutive stimuli is thought to be relatively longer or shorter than its actual elapsed time, due to the spatial/auditory/tactile separation between each consecutive stimuli. The kappa effect can be displayed when considering a journey made in two parts that each take an equal amount of time. When mentally comparing these two sub-journeys, the part that covers more distance may appear to take longer than the part covering less distance, even though they take an equal amount of time.