OPTICAL STUDIES OF NEURON ACTIVITY AND ORGANIZATION

描述（改编自申请人的摘要）：了解如何 神经系统产生一种行为需要大脑的信息， 几个层次。 拟议的实验旨在解决相对 关于鳃如何撤回的三个方面的未探讨的问题 反射由腹神经节产生。 拟议 实验利用相对简单的神经网络的几个优点， 系统 鳃回缩反射的一个显著特征是其 可塑性 习惯化和敏感化都已经在 许多实验室;现在有证据表明NMDA受体的存在 依赖性LTP 感觉神经元轴突终末在这一过程中所起的作用 将研究行为可塑性。 电压敏感染料和 钙指示剂染料将被用来调查的传播 动作电位进入神经末梢和随后的钙进入 确定这些过程在解释行为过程中的作用。 可塑性 23组中间神经元被认为参与了 鳃回缩反射 因此，到目前为止， 其中只有一个是已知的。 对于每个中间神经元组，细胞将是 超极化和/或杀死，以确定去除对细胞的影响。 其他神经元的活动和行为。 细胞将被驱动到 确定跟随神经元的数量和位置。 几百 腹神经节中的神经元对虹吸管的轻微触摸做出反应 皮肤使用由虹吸皮肤组成的相当简化的体外制剂， 腹神经节和鳃。 同样数量的神经元是否会 在完整的动物身上有相似的尖峰模式吗 反应是否因 习惯化和敏感化的过程吗 我们现有的光学方法 已广泛应用于两个临床领域。 一是 跟踪心脏中动作电位的传播， 心律不齐 第二，研究癫痫活动的起源和传播 在完整的大脑和大脑切片中。 最近，这些方法 被用于第三个领域，确定皮层的位置， 接受癫痫手术的患者的语言区。

DESCRIPTION (Adapted from applicant's abstract): An understanding of how a nervous system generates a behavior requires information about the brain at several levels. The proposed experiments are aimed at addressing relatively unexplored questions concerning three aspects of how the gill withdrawal reflex is generated by the Aplysia abdominal ganglion. The proposed experiments make use of several advantages of the relatively simple nervous system. One striking feature of the gill withdrawal reflex is its plasticity. Both habituation and sensitization have been demonstrated in many laboratories; now there is evidence for the presence of NMDA receptor dependent LTP. The role that the sensory neuron axon terminals play in this behavioral plasticity will be investigated. Voltage sensitive dyes and calcium indicator dyes will be used to investigate the propagation of the action potential into the nerve terminal and the subsequent calcium entry to determine the role of these processes in explaining the behavioral plasticity. Twenty-three groups of interneurons are thought to participate in the gill withdrawal reflex. Thus, far the quantitative contribution of only one of these is known. For each interneuron group, the cell(s) will be hyperpolarized and/or killed to determine the effect of removal on the activity of other neurons and on the behavior. The cells will be driven to determine the number and location of follower neurons. Several hundred neurons in the abdominal ganglion respond to a light touch to the siphon skin using a rather reduced in vitro preparation comprised of siphon skin, abdominal ganglion, and gill. Does a similar number of neurons respond with similar spike patterns in the intact animal? Is the response altered by habituation and sensitization in the same way? The optical methods we have developed have been extensively used in two clinical areas. First, to follow the propagation of the action potential in the heart to study arrhythmias. Second, to study the origins and spread of epileptic activity in intact brains and in brain slices. More recently, these methods have been used in a third area, the determination of the location of cortical speech areas in patients undergoing surgery for epilepsy.