Bell C C
J Exp Biol. 1989 Sep;146:229-53. doi: 10.1242/jeb.146.1.229.
Weakly electric fish use their electrosensory systems for electrocommunication, active electrolocation and low-frequency passive electrolocation. In electric fish of the family Mormyridae, these three purposes are mediated by separate classes of electroreceptors: electrocommunication by Knollenorgan electroreceptors, active electrolocation by Mormyromast electroreceptors and low-frequency passive electrolocation by ampullary electroreceptors. The primary afferent fibres from each class of electroreceptors terminate in a separate central region. Thus, the mormyrid electrosensory system has three anatomically and functionally distinct subsystems. This review describes the sensory coding and initial processing in each of the three subsystems, with an emphasis on the Knollenorgan and Mormyromast subsystems. The Knollenorgan subsystem is specialized for the measurement of temporal information but appears to ignore both intensity and spatial information. In contrast, the Mormyromast subsystem is specialized for the measurement of both intensity and spatial information. The morphological and physiological characteristics of the primary afferents and their central projection regions are quite different for the two subsystems and reflect the type of information which the subsystems preserve. This review also describes the electric organ corollary discharge (EOCD) effects which are present in the central projection regions of each of the three electrosensory subsystems. These EOCD effects are driven by the motor command that drives the electric organ to discharge. The EOCD effects are different in each of the three subsystems and these differences reflect differences in both the pattern and significance of the sensory information that is evoked by the fish's own electric organ discharge. Some of the EOCD effects are invariant, whereas others are plastic and depend on previous afferent input. The mormyrid work is placed within two general contexts: (a) the measurement of time and intensity in sensory systems, and (b) the various roles of motor command (efferent) signals and self-induced sensory (reafferent) signals in sensorimotor systems.
弱电鱼利用它们的电感应系统进行电通信、主动电定位和低频被动电定位。在长颌鱼科的电鱼中，这三种功能由不同类别的电感受器介导：电通信由壶腹器官电感受器介导，主动电定位由长颌鱼电感受器介导，低频被动电定位由壶腹电感受器介导。来自每类电感受器的初级传入纤维终止于一个单独的中枢区域。因此，长颌鱼的电感应系统有三个在解剖学和功能上不同的子系统。这篇综述描述了这三个子系统中每个子系统的感觉编码和初始处理，重点是壶腹器官和长颌鱼电感受器子系统。壶腹器官子系统专门用于测量时间信息，但似乎忽略了强度和空间信息。相比之下，长颌鱼电感受器子系统专门用于测量强度和空间信息。这两个子系统的初级传入纤维及其中枢投射区域的形态和生理特征有很大不同，反映了子系统所保留的信息类型。这篇综述还描述了电器官伴随放电（EOCD）效应，这些效应存在于三个电感应子系统中每个子系统的中枢投射区域。这些EOCD效应由驱动电器官放电的运动指令驱动。这三个子系统中的EOCD效应各不相同，这些差异反映了鱼自身电器官放电所诱发的感觉信息在模式和意义上的差异。一些EOCD效应是不变的，而另一些则是可塑性的，取决于先前的传入输入。长颌鱼的研究工作置于两个一般背景下：（a）感觉系统中时间和强度的测量，以及（b）运动指令（传出）信号和自我诱发的感觉（再传入）信号在感觉运动系统中的各种作用。
