Аннотация:1a variant of which is shown in Fig. 1. Our visual system opts for a simple interpretation based on local relationships within the figure, rather than choosing a complex, yet correct, interpretation that takes the entire figure into account. We observe that each stair that is one step clockwise from its neighbor is also one step downward, and so we perceive the staircase as eternally descending. In principle, we could instead perceive the figure correctly as depicting four sets of stairs that are discontinuous, and viewed from a unique perspective—however such a percept never occurs. This paper explores an analogous set of auditory figures that are composed of patterns that appear to ascend or descend endlessly in pitch. Here also, our perceptual system opts for impossible but simple interpretations, based on our perception of local motion in a particular direction–either upward or downward. These sound patterns are not mere curiosities; rather they provide important information concerning general characteristics of pitch perception. Pitch as a two-dimensional attribute By analogy with real-world staircases, pitch is often viewed as extending along a one-dimensional continuum of pitch
