INFORMATION PROCESSING IN LAMINATED NEURONAL NETWORKS

我们打算继续研究感官信息处理和 控制电鱼的简单行为反应。 我们选择 电感觉作为探索基本神经元的模型系统 设计特点，这似乎也涉及到更复杂的感官 系统，如哺乳动物的听觉和视觉。 特别感兴趣的 是分层神经元中刺激空间的有序表示 将某些刺激变量沿沿着特定轴映射到 层压平面和处理刺激的不同方面 复杂性由位于不同层的专门神经元组成。 通过 通过连续的高级中枢神经系统 刺激处理，我们打算达到电机输出水平，从而 提供了一个完整的神经元理论来控制一个简单的行为， 反应 对于Eigenmannia中的干扰避免响应，该目标是 现在触手可及。 本提案侧重于三个项目： 1.传入信息的表征在多种神经元中的意义 映射，例如相同的初级感觉传入神经的投射 三个独立的、按躯体位置排列的脑图。 这 研究涉及细胞内记录和标记所有可用的 细胞类型，以研究其在各种刺激制度下的动态特性 和它们的解剖结构。 三张地图的区别 应该能为它们的功能特化提供线索 2.中脑下行性反复输入的意义 小脑到后脑的所有三个电感觉地图。 的影响 小病变的动态特性的确定细胞类型，以及 将研究整个动物的反应。 3.延髓电器官起搏器的组织结构。 虽然 不是一个严格的层状结构，这个核由两个松散的 分离类型的电耦合，有节奏地放电细胞 控制着电子琴。 调查极端的原因 其节律的稳定性，将进行生理实验 完整的制备物，保存在切片室中的离体起搏器上 以及在组织培养中生长的起搏细胞上。 这些研究将涉及 双细胞内记录和标记的耦合细胞和解剖 调查他们的关系。

We intend to continue our studies on sensory information processing and the control of simple behavioral responses in electric fish. We have chosen the electric sense as a model system for the exploration of basic neuronal design features which also appear to be involved in more complex sensory systems, such as audition and vision in mammals. Of particular interest are ordered representations of stimulus spaces in laminated neuronal networks which map certain stimulus variables along particular axes within the plane of lamination and process different aspects of the stimulus complexity by specialized neurons located in different layers. By advancing through successively higher-order central nervous stations of stimulus processing, we intend to reach the motor output level and thus to provide a complete neuronal theory for the control of a simple behavioral response. For the Jamming Avoidance Response in Eigenmannia, this goal is now within reach. This proposal focuses upon three projects: 1. The significance of representations of afferent information in multiple maps, such as the projections of identical primary electrosensory afferents to three separate, somatotopically ordered maps in the hindbrain. This research involves intracellular recording and labelling of all available cell types to study their dynamic properties under various stimulus regimes and their anatomical architecture. Differences between the three maps should yield clues for their functional specialization. 2. The significance of descending recurrent input from midbrain and cerebellum to all three electrosensory maps in the hindbrain. The effects of small lesions upon dynamic properties of identified cell types as well as upon responses of the whole animal will be studied. 3. The organization of the medullary electric organ pacemaker. Although not a strictly laminated structure, this nucleus consists of two loosely segregated types of electrically coupled, rhythmically discharging cells which control the electric organ. To investigate causes for the extreme stability of its rhythm, physiological experiments will be conducted on intact preparations, on excised pacemakers maintained in a slice chamber and on pacemaker cells grown in tissue culture. These studies will involve dual intracellular recording and labelling of coupled cells and anatomical investigation of their connections.