KembaraXtra-Psychology – Barber’s Pole Effect


The barber’s pole effect is a motion illusion in which diagonal stripes on a rotating surface appear to move vertically or horizontally depending on the orientation of the viewing window. Although the physical motion of the stripes is identical, perceptual constraints imposed by the visual frame bias the perceived direction of movement. This effect highlights how motion perception is shaped by contextual boundaries and directional assumptions made by the visual system.