美国霍华德·休斯医学院Joshua T. Dudman等研究人员合作发现，海马对觅食轨迹的表征取决于空间背景。相关论文于2022年11月29日发表在《自然—神经科学》杂志上。
研究人员训练了小鼠在一个物理竞技场中导航到一个隐藏的目标，或操纵操纵杆到一个虚拟的目标，来收集延迟的奖赏。在导航背景下，自由移动小鼠的钙成像显示，同步CA1的重新激活是回顾性的，对评估先前的导航轨迹很重要。在非导航背景下，重新激活是前瞻性的，对操纵杆轨迹的启动很重要，即使是在两种背景下训练的同一动物。一个共同的学习算法很好地解释了轨迹对新目标的适应，其中海马活动对强化学习计算的贡献是不一样的，取决于空间环境。
据介绍，动物在空间性、导航性背景和关系性、非导航性背景下学习奖励的轨迹。海马活动的同步再激活被认为是回忆和评价学习轨迹的关键。海马表征是否在不同的空间和关系背景下对依赖经验的轨迹学习有不同的贡献仍未知。
附：英文原文
Title: Hippocampal representations of foraging trajectories depend upon spatial context
Author: Jiang, Wan-Chen, Xu, Shengjin, Dudman, Joshua T.
Issue&Volume: 2022-11-29
Abstract: Animals learn trajectories to rewards in both spatial, navigational contexts and relational, non-navigational contexts. Synchronous reactivation of hippocampal activity is thought to be critical for recall and evaluation of trajectories for learning. Do hippocampal representations differentially contribute to experience-dependent learning of trajectories across spatial and relational contexts In this study, we trained mice to navigate to a hidden target in a physical arena or manipulate a joystick to a virtual target to collect delayed rewards. In a navigational context, calcium imaging in freely moving mice revealed that synchronous CA1 reactivation was retrospective and important for evaluation of prior navigational trajectories. In a non-navigational context, reactivation was prospective and important for initiation of joystick trajectories, even in the same animals trained in both contexts. Adaptation of trajectories to a new target was well-explained by a common learning algorithm in which hippocampal activity makes dissociable contributions to reinforcement learning computations depending upon spatial context.
DOI: 10.1038/s41593-022-01201-7
Source: https://www.nature.com/articles/s41593-022-01201-7
来源：科学网 小柯机器人