According to Coren, the well known Müller-Lyer illusion can be explained within this framework. The outwardly turned wings in Müller-Lyer display shift the COG outward from each vertex, while the inwardly turned wings in this figure shift the COG inward. This influences both saccade length from vertex to vertex as well as the apparent length of the central line segments. The influence of COG on efferent readiness to execute eye movements, Coren argues (1986: 400–403), also explains why the line segments in the Müller-Lyer display can be replaced with small dots while leaving the illusion intact as well as the effects of varying wing length and wing angle on the magnitude of the illusion.