ASSOCIATIVE INFORMATION PROCESSING: CELLULAR MECHANISMS

长期目标是分析潜在的细胞机制 神经系统的两个重要能力：(1) 将给定的刺激与新的运动反应(刺激-反应)相关联 或S-R学习)，以及(2)长期感觉可调整性。这一目标 需要制定准备工作，包括明确定义的行为 改变和识别的神经元网络，允许直接分析 生理机制。基于初步研究，使用 完整的海生腹足类海兔的虹吸、尾巴、头部和附足 并将开发半完整的准备工作，显示收购 头部或头部旁刺激配对后的新虹吸反应 尾巴刺激。S-R条件反射的电生理相关性研究 将在已鉴定的虹吸运动神经元和中间神经元中进行检查。二 将检验开发新型S-R连接的假设 使用细胞内记录、电压钳和量子分析 技巧。长期感觉记忆将在中心进行研究 以及顶叶旁感觉神经元的外周突起，这为 感官分析的优势。联想的一般假设是 感觉系统中的信息存储利用了进化的机制 将测试受伤后的感觉补偿。一个人的贡献 特定的细胞联合机制--活性依赖的外源性 调制(ADEM)-将测试对感官的可调性。几个 潜在的与ADEM相关的信令有效性增强 联合条件反射和受损伤的感受场 检查：突触易化，中枢和/或外周增加 兴奋性，以及外周和/或中央突起的萌发。这些 研究应该提供关于一般学习机制的基本信息， 感觉补偿和神经元再生，最终可能 有助于理解正常和不正常的生理 人类神经系统内的可塑性。

The long-term objective is to analyze the cellular mechanisms underlying two important capabilities of the nervous system: (1) the ability to associate a given stimulus with a novel motor response (stimulus-response or S-R learning), and (2) long-term sensory modifiability. This objective requires the development of preparations, involving well-defined behavioral alterations and identified neuronal networks, that permit direct analysis of physiological mechanisms. Building on preliminary studies using the siphon, tail, head, and parapodia of the marine gastropod, Aplysia, intact and semi-intact preparations will be developed that show the acquisition of novel siphon responses after pairing parapodial stimulation with head or tail stimulation. Electrophysiological correlates of this S-R conditioning will be examined in identified siphon motor neurons and interneurons. Two hypotheses for the development of novel S-R connections will be tested using intracellular recording, voltage clamp, and quantal analysis techniques. Long-term sensory memory will be investigated in the central and peripheral processes of parapodial sensory neurons, which offer special advantages for sensory analysis. The general hypothesis that associative information storage in sensory systems makes use of mechanisms evolved for sensory compensation after injury will be tested. The contribution of a specific cellular associative mechanism - activity-dependent extrinsic modulation (ADEM) - to sensory modifiability will be tested. Several potential ADEM-related enhancements of signaling effectiveness produced by associative conditioning and by injury of the receptive field will be examined: synaptic facilitation, increased central and/or peripheral excitability, and sprouting of peripheral and/or central processes. These studies should provide basic information on general mechanisms of learning, sensory compensation, and neuronal regeneration that may eventually contribute to an understanding of normal and abnormal physiological plasticity within the human nervous system.