Stereoscopically sensitive behaviour without correspondence

Abstract:
Stereoscopic vision, or stereopsis, is generally assumed to require stereo correspondence, i.e. identifying which point in the left eye’s image corresponds to the same scene object as a given point in the right. However, the discovery of stereopsis in small-brained animals such as the praying mantis motivates us to think about what can be achieved with simpler forms of stereopsis. Insect stereopsis likely evolved to produce simple behaviour, such as orienting towards the closer of two objects or triggering a strike when prey comes within range, rather than to achieve a rich perception of scene depth. I will show that this sort of adaptive behaviour can be produced with very basic stereoscopic algorithms which make no attempt to achieve fusion or correspondence, or to produce even a coarse map of depth across the visual field. Such algorithms may be all that is required for insects, and may also prove useful in some autonomous applications.