Processing of infrared signals in the central nervous system of the western diamondback rattlesnake

一些蛇物种，如蟒蛇、蟒蛇和蟒蛇，通过一种被称为坑器的特殊器官在红外(IR)光谱中感知电磁辐射。由于小窝器官开口的宽度和红外感受器的数量较少(约6000)，所得到的图像具有较差的分辨率，几乎没有关于各个对象的信息。然而，即使在完全黑暗的情况下，这些蛇也能够对猎物进行快速而准确的攻击。然而，目前还不清楚蛇是否使用神经元过程来有效地从这张低分辨率的红外图像中重建信息。因此，我们将研究红外通路的核(外侧降束核，LTTD；网状核Caloris)的潜在图像处理功能。实现侧抑制的一个可能的候选者是LTTD，因此它可以被认为是视觉系统的视网膜的类似物。在视觉顶盖水平上，红外信息由双峰神经元以独特的方式整合到视觉系统中。在那里，红外系统的低分辨率图像必须被整合到视觉系统的高分辨率图像中。为了详细研究这一整合过程，需要首先揭示单峰IR通路中的先验信息处理。因此，本研究项目的第二个目标是研究针对高等脑区多模式整合的毒蛇红外系统中图像处理的基本原理。此外，还将研究视顶盖与峡部系统的核之间的相互作用。这个网络为专注于与动物最相关的环境刺激提供了基础。由于IR系统在毒蛇对环境的感知中起着至关重要的作用，因此IR系统很可能也影响峡部核团。

Some snake species such as pit vipers, boas and pythons perceive electromagnetic radiation in the infrared (IR) spectrum through a special organ known as the pit organ. Due to the width of the pit organ opening and the low number of infrared receptors (approx. 6000), the resulting image has a poor resolution with little information about the respective object. However, these snakes are able to perform a fast and precise strike towards their prey even in complete darkness. It is however still unknown whether the snakes use neuronal processes to effectively reconstruct information out of this low-resolution IR-image. We will thus investigate the nuclei of the infrared pathway (Nucleus of the lateral descending tract, LTTD; Nucleus reticularis caloris) in respect to potential image processing functions. A likely candidate for the implementation of lateral inhibition is the LTTD, which could therefore be considered as an analogue to the retina of the visual system. At the level of optic tectum infrared information is integrated by bimodal neurons into the visual system in a unique way. There, the lowly resolved image of the IR-system has to be integrated into the high-resolution image of the visual system. For a detailed investigation of this integrative process, prior information processing in the unimodal IR-pathway needs to be revealed first. Therefore, a second aim of this research project is to investigate the basic principles of image processing in the IR-System of pit vipers in respect to multimodal integration in higher brain areas. In addition, the interaction of the optic tectum with nuclei of the isthmic system will be investigated. This network provides the basis for focusing on the environmental stimulus most relevant for the animal. Since the IR-System plays a crucial role for pit vipers in perception of the environment, it is likely that the IR-System also influences the isthmic nuclei.