OPTICAL STUDIES OF NEURON ACTIVITY & ORGANIZATION

该提案有两个长期目标。第一，要 详细了解神经系统是如何简单的 能够产生行为以及这些神经系统是如何 能够完成简单形式的学习。第二个是 了解癫痫发作期间大脑皮层发生了什么。在……里面 为了更好地实现这些科学目标，我们还拥有 改进光学技术的方法学目标 监测神经元的活动。 我们一直在使用光学方法来监测神经元的活动 退鳃反射时的海兔腹神经节。 我们的初步结果表明，250到420个神经元 在神经节中被机械刺激激活 虹吸。然而，这一估计来自一段录音，该录音 可能已经完成了35%。我们建议进行实验，以改善 录音的完整性，实验以允许初步 识别其中许多神经元，并进行分析以使我们 为了跟踪单个神经元在一系列 涉及习惯化和敏感化的试验。我们还计划 实验试图看看同样的行为可塑性是否可以 用更少的神经元就能实现。如果这是成功的，我们建议 建立一个神经元相互作用的模型，产生 行为。 我们已经能够监测荷包牡丹碱诱导的活性 大鼠体感觉皮层发作间期癫痫样放电。 我们的结果在两个方面令人惊讶。首先，他们表示 光学测量和球状电极 测量结果可能大相径庭。第二，他们 表明两者之间存在质的差异 感觉刺激诱发的放电和自发放电 出院。我们的首要目标是确认这些结果。那我们 计划局部应用荷包牡丹碱来研究扩散(或 无扩散)癫痫活动远离被治疗者 区域。最后，我们计划从这两个方面同时进行测量 荷包牡丹碱治疗对侧和未治疗对侧 躯体感觉皮质。这些实验旨在引导 在更复杂的模型(灵长类)中进行测量 人类疾病。这些实验也可能导致使用 用于确定位置的光学监测技术 外科病人中的癫痫灶。

There are two long-term objectives of the proposal. First, to understand in neuronal detail how simpler nervous systems are able to generate behaviors and how these nervous systems are able to accomplish simple forms of learning. The second is to understand what happens in cortex during epileptic seizures. In order to better accomplish these scientific goals, we also have the methodological goal of improving optical techniques for monitoring neuron activity. We have been using optical methods to monitor neuron activity in the Aplysia abdominal ganglion during the gill-withdrawal reflex. Our preliminary results suggest that between 250 and 420 neurons in the ganglion are activated by a mechanical stimulus to the siphon. However this estimate comes from a recording that is perhaps 35% complete. We propose experiments to improve the completeness of the recording, experiments to allow preliminary identification of many of these neurons, and analyses to allow us to follow the activity of individual neurons during a series of trials involving habituation and sensitization. We also plan experiments to try to see if the same behavioral plasticity can be achieved with fewer neurons. If this is successful we propose to make a model of the neuron interactions that generate the behavior. We have been able to monitor activity in bicuculline induced inter-ictal epileptiform discharges in rat somatosensory cortex. Our results were surprising in two regards. First, they indicated that the optical measurements and the ball electrode measurements could give very disparate results. Second, they indicated that there were qualitative differences between discharges induced by sensory stimulation and spontaneous discharges. Our first aim is to confirm these result. Then we plan a local application of bicuculline to study the spread (or absence of spread) of the epileptic activity away from the treated region. Finally we plan a simultaneous measurement from both the bicuculline treated and the untreated contralateral somatosensory cortex. These experiments are meant to lead toward measurements in more sophisticated models (primates) of the human disease. These experiment may also lead to the use of optical monitoring techniques for determining the location of epileptic foci in surgical patients.