Tracing the Neural Circuitry of Rewarding Brain Stimulation

这项工作将开始绘制大脑回路，这些回路携带奖励信号，据信是当动物成功实现激励目标时产生的，比如在饥饿时寻找食物。这样的信号被认为是为了告诉动物，它目前的行为对它的生存很重要，并加强了这种行为的延续。长期以来，人们一直认为电刺激内侧前脑束可以产生一种有效且不满足的奖赏信号，然而，在这条主要轴突通路之外，这一信号所穿越的电路仍然未知。当暂时麻醉远离前脑束的目标区域时，通过心理生理跟踪内侧前脑束刺激的奖赏幅度的变化，可以揭示携带信号的关键脑区。一旦确定了与奖励相关的靶点，将从电生理学的角度探索这些靶点与刺激部位之间的解剖关系。刺激诱导的神经活动将被跟踪到这些区域，以查看神经信号是否具有已知的传导特性来表征假定的奖励信号，以及靶区是否直接或间接(即，跨突触地)与内侧前脑束相连。这个项目将增加我们对与奖励有关的大脑回路的理解，长期目标是了解它们在消费行为和其他动机行为中的作用。

This work will begin to map brain circuits that carry the reward signal believed to be generated when animals successfully meet motivational goals, such as finding food when hungry. Such a signal is thought to inform the animal that its current behavior is important to its survival, and to reinforce the continuation of that behavior. Electrical stimulation of the medial forebrain bundle has long been believed to create a potent and non-satiating version of the reward signal, yet the circuitry traversed by this signal outside of this major axon pathway is still unknown. Brain areas critical to carrying the signal will be revealed by psychophysically tracking changes in the reward magnitude of medial forebrain bundle stimulation when target areas distant from the bundle are temporarily anesthetized. Once reward-relevant targets are identified, the anatomical relationship of these targets to the stimulation sites will be explored electrophysiologically. The stimulation-induced neural activity wilkl be followed to those areas to see whether the neural signals have conduction properties known to characterize the putative reward signal, and whether the target areas are directly or indirectly (i.e., transynaptically) linked to the medial forebrain bundle. This project will increase our understanding of brain circuits involved in reward, with a long term goal of understanding their role in consumptive and other motivated behaviors.