Central Processing of Electrosensory Information in MormyridFish

某些鱼被称为“弱电鱼”，因为它们有电器官，可以产生少量的重复放电，在周围的水中产生电场。这种鱼的皮肤上有电感受器，能够探测到电场的时间和空间分布，并可以利用这些信息来感知环境中的物体，并进行交流。电感觉信息的中央处理的第一阶段是大脑中称为电感觉侧线叶（ELL）的部分；这个脑叶有一个皮层结构，其细胞组织与小脑相似。其他系统也投射到ELL，包括来自其他系统的感觉输入，如侧线器官的机械感受器，从更高层次的电感觉系统下降的信号，以及一组称为“必然放电”的特定信号，每次电放电发生时都会发生，并且被认为提供了一个有用的参考信号，用于解释来自环境的电感觉输入如何从“预期”输入改变。本项目采用电生理细胞记录和解剖方法完成对ELL细胞类型的研究；建立下一个高级中央站的主要细胞类别，称为突前核，以及它们如何投射到ELL；并观察ELL的非电感觉输入是否会根据与电感觉输入的先前关联而改变。这项工作的结果对于深入了解调节传入感觉信号的中央输入的可能功能，以及阐明小脑等结构中功能电路的基本原理非常重要。

Certain fish are known as "weakly electric fish" because they have electric organs that generate a small repetitive discharge that creates an electric field in the surrounding water. The fish has electrosensory receptors in the skin which are able to detect the timing and the spatial distribution of the electrical field, and can use this information for sensing objects in the environment, and for communication. The first stage of central processing of the electrosensory information is a part of the brain called the electrosensory lateral-line lobe (ELL); this lobe has a cortical structure with a cellular organization similar to that found in the cerebellum. Other systems also project to the ELL, including sensory input from other systems such as mechanoreceptors of the lateral-line organ, signals descending from higher levels of the electrosensory system, and a particular set of signals called "corollary discharge" which occurs every time the electric orgal discharge occurs, and is believed to provide a reference signal useful to interpreting how the electrosensory input from the environment may be changed from the "expected" input. This project uses electrophysiological cellular recording and anatomical methods to complete a study of the cell types found in the ELL; to establish the major cell classes of the next higher central station called the pre-eminential nucleus, and how they project to the ELL; and to see whether the non-electrosensory inputs to the ELL can change depending on prior association with electrosensory input. Results from this work will be important for insights into the possible functions of central inputs that modulate incoming sensory signals, and in clarifying fundamental principles of functional circuitry in structures like the cerebellum.