Laboratory of Neuroscience, University of Oviedo, Oviedo, Spain.
J Neurosci Res. 2012 Mar;90(3):715-20. doi: 10.1002/jnr.22774. Epub 2011 Oct 19.
The hippocampus and the striatum have traditionally been considered as part of different and independent memory systems. However, there is evidence that supports a functional interaction between the hippocampus and the dorsal striatum at least in particular learning tasks. Here, we evaluated the functional contribution of both brain regions in a visual discrimination learning task using cytochrome c oxidase (CO) quantitative histochemistry. Compared with other brain metabolic mapping techniques, CO activity reflects steady-state neuronal energy demand. Rats were trained for 6 days in a water T-maze to find a hidden escape platform associated with an intramaze visual cue. A control group of animals swam for an equivalent amount of time compared as the trained group but without any escape platform available. After finishing the behavioral task, CO activity was measured in subdivisions of the dorsal hippocampus and the dorsal striatum in both groups. Results show significantly higher CO activity in the CA1 area and the dentate gyrus of the dorsal hippocampus in the trained rats compared with the control group. In addition, a significant negative functional cross-correlation between area CA1 of the dorsal hippocampus and the anterodorsal striatum was found. Our results support current theories on competitive interaction of different memory systems during visual discrimination learning.
海马体和纹状体传统上被认为是不同且独立的记忆系统的一部分。然而，有证据表明，在某些特定的学习任务中，海马体和背侧纹状体之间存在功能相互作用。在这里，我们使用细胞色素 c 氧化酶（CO）定量组织化学评估了这两个脑区在视觉辨别学习任务中的功能贡献。与其他脑代谢映射技术相比，CO 活性反映了稳定状态神经元的能量需求。大鼠在水 T 迷宫中接受 6 天的训练，以找到与迷宫内部视觉线索相关的隐藏逃生平台。一组对照组动物游泳的时间与训练组相同，但没有可用的逃生平台。完成行为任务后，在两组动物的背侧海马体和背侧纹状体的细分区域中测量 CO 活性。结果显示，与对照组相比，训练组大鼠背侧海马体的 CA1 区和齿状回的 CO 活性显著升高。此外，还发现背侧海马体的 CA1 区和前背侧纹状体之间存在显著的负功能交叉相关。我们的结果支持了关于视觉辨别学习过程中不同记忆系统竞争相互作用的当前理论。
