Insect vision based motion detection

Significant progress has been made in the understanding of the insect visual system over the past 40 years. In the field of motion detection particularly, an elementary motion detector (EMD) which is based on a non-linear asymmetric interaction between signals mediated by adjacent points of the sampling lattice of the insect eye was discovered. Gradually, the EMD has been become an essential principle of visual motion detection exhibited in biological motion vision from insects to human beings. An empirical model named the template model was proposed by Horridge (1990). However, there is no unique way of interpreting the physical meanings of templates responding to motion. This paper attempts to resolve the problem of determining the meanings of templates by firstly proposing a directional selectivity function which is subsequently employed to identify template responses induced by coherent motion.