Department of Life Sciences, National Cheng Kung University, Tainan 70101, Taiwan
Department of Life Sciences, National Cheng Kung University, Tainan 70101, Taiwan.
J Exp Biol. 2020 Nov 26;223(Pt 22):jeb219832. doi: 10.1242/jeb.219832.
Stomatopods, or mantis shrimp, are the only animal group known to possess circular polarization vision along with linear polarization vision. By using the rhabdomere of a distally located photoreceptor as a wave retarder, the eyes of mantis shrimp are able to convert circularly polarized light into linearly polarized light. As a result, their circular polarization vision is based on the linearly polarized light-sensitive photoreceptors commonly found in many arthropods. To investigate how linearly and circularly polarized light signals might be processed, we presented a dynamic polarized light stimulus while recording from photoreceptors or lamina neurons in intact mantis shrimp The results indicate that all the circularly polarized light-sensitive photoreceptors also showed differential responses to the changing e-vector angle of linearly polarized light. When stimulated with linearly polarized light of varying e-vector angle, most photoreceptors produced a concordant sinusoidal response. In contrast, some lamina neurons doubled the response frequency in reacting to linearly polarized light. These responses resembled a rectified sum of two-channel linear polarization-sensitive photoreceptors, indicating that polarization visual signals are processed at or before the first optic lobe. Noticeably, within the lamina, there was one type of neuron that showed a steady depolarization response to all stimuli except right-handed circularly polarized light. Together, our findings suggest that, between the photoreceptors and lamina neurons, linearly and circularly polarized light may be processed in parallel and differently from one another.
十足目动物，又称螳螂虾，是目前已知唯一同时具有圆偏振光视觉和线偏振光视觉的动物群体。通过利用远侧光感受器的光感受器节作为波延迟器，螳螂虾的眼睛能够将圆偏振光转换为线偏振光。因此，它们的圆偏振光视觉基于许多节肢动物中常见的对线偏振光敏感的光感受器。为了研究线性和圆偏振光信号如何被处理，我们在完整的螳螂虾中记录光感受器或神经节层神经元时，呈现动态偏振光刺激。结果表明，所有圆偏振光敏感的光感受器对线性偏振光的 e-矢量角度变化也表现出不同的反应。当用不同 e-矢量角度的线偏振光刺激时，大多数光感受器产生一致的正弦响应。相比之下，一些神经节层神经元在对线偏振光的反应中，将响应频率增加了一倍。这些反应类似于两个通道线性偏振敏感光感受器的整流和，表明偏振视觉信号在第一视神经叶或之前进行处理。值得注意的是，在神经节层中，有一种类型的神经元除了右手圆偏振光外，对所有刺激都表现出稳定的去极化反应。总之，我们的发现表明，在线性和圆偏振光的处理方面，在光感受器和神经节层神经元之间，可能存在平行且不同的处理方式。
