The Role of Photoreceptor Light Sensitivity in Expression of Classical Conditioning

贝克威尔IBN-0077509海鸥Hermissenda crassicornis是研究联想学习的模式系统，因为它与哺乳动物分享了经典条件反射的特性。在Hermissenda中，已经确定了单个脑细胞，其中细胞属性的变化与动物学习行为的变化相关。具体地说，由于经典的光和湍流条件作用，B型光感受器表现出兴奋性的增加。B型光感受器的兴奋性受流经细胞膜的电流的影响。对这一尚未充分描述的海流的测量是该项目的目标之一。联想学习行为的表达依赖于A型和B型光感受器对光的反应。这种相互作用受到流经A型光感受器膜上的光感应电流的影响。因此，该项目的第二个目标是根据不同强度和持续时间的光线测量这一电流。这项研究的第三个也是最后一个目标是开发一个关于两类(A型和B型)光感受器及其相互作用的计算机模型。模型模拟被用来评估这两种类型的光感受器对光的反应的输出，以及由于B型光感受器的兴奋性增加而导致的输出的变化。这个项目将对我们了解人们是如何学习的有很大的帮助。经典条件反射，也被称为巴甫洛夫条件反射，被广泛研究，因为它是存在于许多不同物种中的一种联想学习形式。细胞兴奋性的改变被认为是联想学习的一般机制，因为它已经在哺乳动物的脑细胞中检测到，这些细胞已经被经典地限制了。然而，细胞兴奋性变化和动物行为变化之间的途径还不完全清楚。这些证据表明，学习行为的表达源于对神经元组之间复杂相互作用的调制。这个项目开始阐明细胞属性的变化如何调节参与经典条件反射行为的神经元网络。

Lay SummaryBlackwellIBN-0077509The seaslug, Hermissenda crassicornis, is a model system for studying associative learning because it shares properties of classical conditioning with mammals. In Hermissenda, individual brain cells have been identified in which a change in cell properties is correlated with a change in animal learning behavior . Specifically, the type B class of photoreceptors shows an increase in excitability consequent to classical conditioning with light and turbulence. The excitability of the type B photoreceptor is affected by current flowing across the cell membrane in response to light. The measurement of this current, which has not been adequately characterized, is one goal of this project. The expression of associative learning behavior depends on the interaction between type A and type B photoreceptors in response to light. This interaction is affected by the light-induced current flowing across the membrane of the type A photoreceptors. Thus, a second goal of this project is to measure this current in response to light of various intensities and durations. The third and final goal of this research is to develop a computer model of both (type A and type B) classes of photoreceptors and their interaction. Model simulations are used to evaluate the output of both types of photoreceptors in response to light, and the change in output consequent to an increase in excitability in the type B photoreceptor.This project will significantly contribute to our knowledge of how people learn. Classical conditioning, also known as Pavlovian conditioning, is studied extensively because it is a form of associative learning present in many different species. A change in cell excitability is thought to be a general mechanism of associative learning because it has been detected in brain cells of mammals which have been classically conditioned. However, the pathway between change in cell excitability and change in animal behavior is not fully understood. These is evidence that expression of learning behavior emanates from modulation of the complex interaction between groups of neurons. This project begins to elucidate how changes in cell properties modulate neuronal networks involved in classical conditioning behavior.