NEURAL BASIS OF MOTIVATED BEHAVIORS

我们研究的长期目标是了解 复杂动机行为的可塑性。 为了实现这一目标，我们建议 去研究那些负责 在一个简单的模型系统中， 加利福尼亚州。 这项研究将利用综合的跨学科 结合解剖学，免疫细胞化学， 电生理学和生化技术， 分析. 我们要研究的主要问题是 利用相同的神经元和肌肉 在执行各种协调行为时 在强度和速度上。 我们建议，这可以通过以下方式实现： 两大类机制。 第一，创造 不同功能的运动回路，通过激活不同的 不同行为的运动神经元的组合，以及 运动神经元的放电模式在这些情况下，当在一个单一的 行为的强度或频率响应变化。 的 第二组假设的机制通过改变比例来运作 和调节性共递质（尤其是神经肽）的组合 和经典的递质作用于肌肉，从而调整 肌肉的特性，以满足特定的行为需求。 一 一个包含这两组机制的概念模型将是 测试，如果正确，将有助于指导未来的作用， 回路选择和神经调节在动机行为中起作用。 这些 研究应该有助于理解动机的神经基础 行为和他们的功能障碍，如常见的精神疾病 比如抑郁症和躁狂症

The long-term goal of our research is to understand the neural basis of plasticity of complex motivated behaviors. Towards this goal, we propose to investigate the circuits and neural mechanisms that are responsible for the generation of feeding behavior in a simple model system, Aplysia californica. This research will utilize an integrated interdisciplinary approach that combines anatomical, immunocytochemical, electrophysiological, and biochemical techniques with a behavioral analysis. The major question we will investigate concerns the ability of an organism to utilize the same neuronal elements and the same muscles in executing a variety of coordinated behaviors each of which can vary in their intensity and speed. We propose that this may be achieved by two major groups of mechanisms. The first, consists of creating different functional motor circuits, through activation of different combinations of motorneurons for different behaviors, and of changes of firing patterns of motorneurons in those cases when within a single behavior either the intensity or the frequency of responding change. The second postulated group of mechanisms operate by changing the proportions and combination of modulatory cotransmitters (especially neuropeptides) and classical transmitters acting on the muscle, thus adjusting the properties of the muscle to meet specific behavioral demands. A conceptual model that incorporates both groups of mechanisms will be tested, and if correct, will help guide future studies of the role that circuit selection and neuromodulation play in motivated behaviors. These studies should facilitate understanding of the neural basis of motivated behaviors and of their dysfunction, as seen in prevalent mental illnesses such as depression and mania.