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Complex tasks like hunting moving prey in an unpredictable environment require high levels of motor and sensory integration. An animal needs to detect and track suitable prey objects, measure their distance and orientation relative to its own position, and finally produce the correct motor output to approach and capture the prey. In the insect brain, the central complex (CX) is one target area where integration is likely to take place. In this study, we performed extracellular multi-unit recordings on the CX of freely hunting praying mantises (Tenodera sinensis). Initially, we recorded the neural activity of freely moving mantises as they hunted live prey. The recordings showed activity in cells that either reflected the mantis's own movements or the actions of a prey individual, which the mantises focused on. In the latter case, the activity increased as the prey moved and decreased when it stopped. Interestingly, cells ignored the movement of the other prey than the one to which the mantis attended. To obtain quantitative data, we generated simulated prey targets presented on an LCD screen positioned below the clear floor of the arena. The simulated target oscillated back and forth at various angles and distances. We identified populations of cells whose activity patterns were strongly linked to the appearance, movement, and relative position of the virtual prey. We refer to these as sensory responses. We also found cells whose activity preceded orientation movement toward the prey. We call these motor responses. Some cells showed both sensory and motor properties. Stimulation through tetrodes in some of the preparations could also generate similar movements. These results suggest the crucial importance of the CX to prey-capture behavior in predatory insects like the praying mantis and, hence, further emphasize its role in behaviorally and ecologically relevant contexts.
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Simulation of the Arthropod Central Complex: Moving Towards Bioinspired Robotic Navigation Control
It is imperative that an animal have the ability to track its own motion within its immediate surroundings. It gives the necessary basis for decision making that leads to appropriate behavioral responses. It is our goal to implement insect-like body tracking capabilities into a robotic controller and have this serve as the first step toward adaptive robotic behavior. In an attempt to tackle the first step of body tracking without GPS or other external information, we have turned to arthropod neurophysiology as inspiration. The insect brain structure called the central complex (CX) is thought to be vital for sensory integration and body position tracking. The mechanisms behind sensory integration are immensely complex, but it was found to be done with an elegant neuronal architecture. Based on this architecture, we assembled a dynamical neural model of the functional core of the central complex, two structures called the protocerebral bridge and the ellipsoid body, in a simulation environment. Using non-spiking neuronal dynamics, our simulation was able to recreate in vivo behavior such as correlating body rotation direction and speed to activity bump dynamics within the ellipsoid body of the central complex. This model serves as the first step towards using idiothetic cues to track body position and orientation determination, which is critical for homing after exploring new environments and other navigational tasks.
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- Award ID(s):
- 1704436
- PAR ID:
- 10076339
- Date Published:
- Journal Name:
- Lecture notes in computer science
- Volume:
- 10928
- ISSN:
- 1611-3349
- Page Range / eLocation ID:
- 370-381
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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