Stereopsis without correspondence

Abstract

Stereopsis has traditionally been considered a complex visual ability, restricted to large-brained animals. The discovery in the 1980s that insects, too, have stereopsis, therefore, challenged theories of stereopsis. How can such simple brains see in three dimensions? A likely answer is that insect stereopsis has evolved to produce simple behaviour, such as orienting towards the closer of two objects or triggering a strike when prey comes within range. Scientific thinking about stereopsis has been unduly anthropomorphic, for example assuming that stereopsis must require binocular fusion or a solution of the stereo correspondence problem. In fact, useful 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. This may explain why some aspects of insect stereopsis seem poorly designed from an engineering point of view: for example, paying no attention to whether interocular contrast or velocities match. Such algorithms demonstrably work well enough in practice for their species, and may prove useful in particular autonomous applications. This article is part of a discussion meeting issue ‘New approaches to 3D vision’.

Individuating Cognitive Characters: Lessons from Praying Mantises and Plants

“…work prompted further empirical testing for stereopsis in a greater range of nonhuman species and for further details of praying mantis stereopsis. In the light of these accumulated results, Nityananda and Read (2017;Nityananda et al 2018;Read 2023; henceforth N&R) initiate conceptual testing by proposing to revise the definition of stereopsis in targeted ways. Their revision reveals the metaphysical impact of including the praying mantis stereopsis phenotype as a determinate of the stereopsis character.…”

New Approaches to 3D Vision

“…Michael Morgan [ 154 ] explores the complexity of disparity processing in humans. By contrast, Jenny Read [ 155 ] explores how an animal with more limited computational capacities, such as the praying mantis, could extract distance information from disparity without the complexities of human vision (such as matching the points in the two eyes or extracting a depth map). Other studies of stereo vision in animals include owls [ 156 ], toads [ 157 ], and cuttlefish [ 158 ].…”

Anatomical organization of the cerebrum of the praying mantis Hierodula membranacea

“…Mantises are ambush predators that rely strongly on vision for hunting and spatial orientation. They are the only insect group known to use stereopsis for distance perception (Nityananda, Tarawneh, et al., 2016; Read, 2023; Rossel, 1983). Their compound eyes provide a nearly full panoramic view and exhibit binocular overlap in the frontal visual field (Rossel, 1979).…”