HEBBIAN PLASTICITY AND CLASSICAL CONDITIONING

这个项目的长期目标是阐明神经元 海洋软体动物海兔的学习记忆机制 卡里福尼卡。这种动物的防御性退缩反射构成了 为此目的的一个有用的系统。这种反射表现出几种形式的 学习，包括古典条件反射。它的神经回路 是撤退反射的基础，特别是它的单突触成分- 感觉神经元和运动神经元之间的突触--相对简单 而且很容易被理解。拟议的实验将集中在一种形式的 突触的可塑性称为Hebbian长时程增强(LTP)。这 突触可塑性的形式，特别是其在CA1中的表现 海马区，与脊椎动物有显著的关系 记忆和认知。最近，一种类型的LTP已被描述用于 细胞培养中的海兔感觉运动型突触(ApLTP) 在力学上与CA1突触的LTP非常相似。具体目标 这一建议的目的是确定apLTP相关进程是否 参与了在海绵的学习。拟议中的实验将利用 年组成海兔中枢神经系统的制剂 涉及一种细胞类似物的电生理实验 戒断反射的经典条件反射。拟议的研究 将作为改善我们对人类学习的理解的基础 和记忆。因此，它可能有助于改善人类的记忆力- 相关疾病，如阿尔茨海默氏症S。

The long-term objective of this project is to elucidate the neuronal mechanisms of learning and memory in the marine mollusk Aplysia californica. The defensive withdrawal reflex of this animal constitutes a useful system for this purpose. The reflex exhibits several forms of learning, including classical conditioning. The neuronal circuitry which underlies the withdrawal reflex, particularly its monosynaptic component- the synapse between the sensory and motor neurons-is relatively simple and well understood. The proposed experiments will focus on a form of synaptic plasticity known as Hebbian long-term potentiation (LTP). This form of synaptic plasticity, particularly its manifestation in the CA1 region of the hippocampus, has been prominently implicated in vertebrate memory and cognition. Recently, a type of LTP has been described for Aplysia sensorimotor synapses in cell culture (apLTP) which appears to be mechanistically quite similar to LTP of CA1 synapses. The specific aim of this proposal is to deterMine whether an apLTP-related process is involved in learning in Aplysia. The proposed experiments will utilize preparations comprising the central nervous system of Aplysia in electrophysiological experiments involving a cellular analogue of classical conditioning of the withdrawal reflex. The proposed research will serve as the basis for improving our understanding of human learning and memory. It may thereby contribute to ameliorating human memory- associated diseases, such as Alzheimer' s.