Tracing the Neural Circuitry of Rewarding Brain Stimulation

这项工作将开始绘制携带奖励信号的大脑回路，这些信号被认为是当动物成功地达到激励目标时产生的，比如饥饿时找到食物。 这种信号被认为是告知动物，它目前的行为对它的生存很重要，并加强了这种行为的持续性。 电刺激内侧前脑束长期以来被认为会产生一种强有力的、不满足的奖赏信号，但这种信号在这个主要轴突通路之外穿过的回路仍然是未知的。 当暂时麻醉远离内侧前脑束的目标区域时，通过精神病理学跟踪内侧前脑束刺激的奖励幅度的变化，将揭示对携带信号至关重要的大脑区域。 一旦识别出奖励相关目标，将在电生理学上探索这些目标与刺激部位的解剖关系。刺激诱导的神经活动将被跟踪到那些区域，以查看神经信号是否具有已知表征推定的奖励信号的传导特性，以及目标区域是否直接或间接（即，transsynaptically）连接到内侧前脑束。这个项目将增加我们对奖励所涉及的大脑回路的理解，长期目标是了解它们在消费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.