Operation System of Insect Brain for Sophisticated Behavior

中国虎甲虫的幼虫是一种埋伏的猎人，体长15-22毫米，生活在地下的隧道中。它伏击猎物，保持头部水平在隧道的开口处。当猎物接近隧道时，幼虫会跳起来咬它。然而，当物体移动到它的跳跃范围（约15 mm）之外时，幼虫会迅速退回隧道深处。这些反应由六对茎中的两对介导。幼虫是如何用如此简单的视觉系统来判断狩猎范围的？通过行为观察证实了通过双目视觉进行的范围估计，其中幼虫向超出正常狩猎范围的物体跳跃，当这些遥远物体的虚拟图像通过棱镜或窄窗形成在幼虫附近时。单目视觉的范围估计也证实了行为实验。视网膜中图像的深度似乎在距离估计中起作用，因为一只幼虫 关于我们 当凹透镜置于其头上时，部分脑干对远距离物体的反应由逃避变为跳跃，延髓神经元（二级视觉中间神经元）的细胞内反应表明，距离敏感性确实发生在大脑的外周部分。比较了延髓神经元对10 mm和50 mm高度运动物体的反应模式。大多数神经元对10 mm和50 mm高度移动的物体有相同的放电模式。少数神经元，然而，表现出距离的敏感性与增加的尖峰放电，以移动的物体，只有在两个高度。上述行为和电生理研究结果表明，单茎幼虫仍保持这种距离敏感性，而四个茎中有三个被封闭。我们的结论是，在虎甲虫幼虫狩猎范围的视觉信息提取外围的图像清晰度的空间格局，并可能集中通过双目视觉。少

The larva of the tiger beetle Cicindela chinensis is an ambushing hunter with a body length of 15-22 mm, that lives in a tunnel in the ground. It ambushes prey, keeping its head horizontal at the opening of the tunnel. When prey approaches the tunnel, the larva jumps to snap at it. When an object moves beyond its jumping range (approximately 15 mm), however, the larva quickly withdraws deep into the tunnel. These responses are mediated by two of six pairs of stemmata. How does the larva judge the hunting range using such a simple visual system? Range estimation by binocular vision was confirmed by behavioral observations, in which larvae jumped towards objects beyond the normal hunting range when virtual images of such distant objects were formed close to the larva by prisms or a narrow window. Range estimation by monocular vision was also confirmed by behavioral experiments. The depth of the image in the retina appears to have a role in distance estimation because a larva with one fun … More ctional stemma, other stemmata being occluded, changed its response to a very distant object from escape to jump when a concave lens was placed above its head.Intracellular responses of medulla neurons (second order visual interneurons) showed that distance sensitivities really occurred in the peripheral part of the brain. Response patterns of medulla neurons to moving objects at heights of 10 mm and 50 mm were compared. The majority of neurons responded to objects moving at heights of 10 mm and 50 mm with the same discharge pattern. A few neurons, however, showed distance sensitivities responding with an increase of spike discharges to moving objects only at either of the two heights. Such distance sensitivities still remained in one-stemma larvae, three of the four stemmata being occluded.Above mentioned behavioral and electrophysiological results suggested. We conclude that visual information about hunting range in the tiger beetle larva is extracted peripherally by the spatial pattern of image clarity, and probably centrally by binocular vision. Less