LEECH LOCAL BENDING: UNDERSTANDING A SENSORY MOTOR LOOP

动物不断地处理和回应环境线索。水蛭非常适合研究感觉运动整合，因为人们可以在它们正在进行的行为中监测它们的神经元活动，并计算出神经元回路的详细连接。此外，水蛭似乎使用与其他感觉运动系统相同的种群编码。为了确定水蛭中枢神经系统使用的矢量计算的性质，电压敏感染料将识别中间神经元并表征运动神经元之间的抑制剂连接如何影响运动控制；所有的连接都将通过电生理学来确认。肌电图将用于测量对水蛭体壁局部触摸的弯曲幅度和方向。然后将在电路中不受抑制的情况下检查弯曲响应。该网络的计算模型将用于测试不同的种群编码策略和去除抑制的效果。总的来说，实验和建模的结果应该确定水蛭神经系统用于处理感觉输入以指导行为输出的代码类型，并将在形成矢量代码时显示抑制功能。

Animals constantly process and respond to environmental cues. Leeches are well suited for studies of sensorimotor integrations because one can monitor their neuronal activity during ongoing behavior and work out detailed connectivity for the neuronal circuits. Moreover, leeches appear to use the same kind of population codes as are found in other sensory- motor systems. To determine the nature of the vector calculations used by the leech CNS, voltage sensitive-dyes will identify interneurons and characterize how inhibitor connections among motor neurons influence motor control; all connections will be confirmed electrophysiologically. Electromyography will be used to measure bend amplitude and direction in response to localized touches delivered to the leech body wall. Then the bending response will be examined without inhibition in the circuit. Computational models of the network will be used to test different population coding strategies and the effects of removing inhibition. Collectively, the results of the experiments and modeling should identify the type of code the leech nervous system uses to process sensory input to direct behavioral output and will show the function of inhibition in forming the vector code.