Neuro-Electronics Research Flanders, Leuven, Belgium; Brain & Cognition, KU Leuven, Leuven, Belgium.
Neuro-Electronics Research Flanders, Leuven, Belgium; Department of Chemistry, KU Leuven, Leuven, Belgium.
Cell Rep. 2023 Aug 29;42(8):112959. doi: 10.1016/j.celrep.2023.112959. Epub 2023 Aug 16.
Previous studies have highlighted an important role for hippocampal sharp-wave ripples in spatial alternation learning, as well as in modulating activity in the medial prefrontal cortex (mPFC). However, the direct influence of hippocampal sharp-wave ripples on mPFC activity during spatial alternation learning has not been investigated. Here, we train Long Evans rats on a three-arm radial maze to perform a sequence of alternations. Three alternation sequences needed to be learned, and while learning a sequence, the activity in the mPFC was inhibited either directly following sharp-wave ripples in the hippocampus (on-time condition) or with a randomized delay (delayed condition). In the on-time condition, the behavioral performance is significantly worse compared to the same animals in the delayed inhibition condition, as measured by a lower correct alternation performance and more perseverative behavior. This indicates that the activity in the mPFC directly following hippocampal sharp-wave ripples is necessary for spatial rule switching.
先前的研究强调了海马体尖波涟漪在空间交替学习中的重要作用，以及在调节内侧前额叶皮层（mPFC）活动中的作用。然而，海马体尖波涟漪对空间交替学习中 mPFC 活动的直接影响尚未得到研究。在这里，我们训练长耳大野鼠在三臂放射状迷津上进行一系列交替。需要学习三个交替序列，在学习一个序列时，mPFC 的活动要么直接在海马体的尖波涟漪之后被抑制（即时条件），要么通过随机延迟被抑制（延迟条件）。在即时条件下，与在延迟抑制条件下的相同动物相比，行为表现明显更差，表现为较低的正确交替性能和更多的坚持行为。这表明海马体尖波涟漪之后 mPFC 的活动对于空间规则转换是必要的。
