Shomrat Tal, Zarrella Ilaria, Fiorito Graziano, Hochner Binyamin
Department of Neurobiology, Institute of Life Sciences and The Interdisciplinary Center for Neural Computation, Hebrew University, 91904 Jerusalem, Israel.
Curr Biol. 2008 Mar 11;18(5):337-42. doi: 10.1016/j.cub.2008.01.056.
Analyzing the processes and neuronal circuitry involved in complex behaviors in phylogenetically remote species can help us understand the evolution and function of these systems. Cephalopods, with their vertebrate-like behaviors but much simpler brains, are ideal for such an analysis. The vertical lobe (VL) of Octopus vulgaris is a pivotal brain station in its learning and memory system. To examine the organization of the learning and memory circuitry and to test whether the LTP that we discovered in the VL is involved in behavioral learning, we tetanized the VL to induce a global synaptic enhancement of the VL pathway. The effects of tetanization on learning and memory of a passive avoidance task were compared to those of transecting the same pathway. Tetanization accelerated and transection slowed short-term learning to avoid attacking a negatively reinforced object. However, both treatments impaired long-term recall the next day. Our results suggest that the learning and memory system in the octopus, as in mammals [9], is separated into short- and long-term memory sites. In the octopus, the two memory sites are not independent; the VL, which mediates long-term memory acquisition through LTP, also modulates the circuitry controlling behavior and short-term learning.
分析系统发育关系较远的物种中复杂行为所涉及的过程和神经回路，有助于我们理解这些系统的进化和功能。头足类动物具有类似脊椎动物的行为，但大脑要简单得多，是进行此类分析的理想对象。普通章鱼的垂直叶（VL）是其学习和记忆系统中的一个关键脑区。为了研究学习和记忆回路的组织，并测试我们在VL中发现的长时程增强（LTP）是否参与行为学习，我们对VL进行强直刺激以诱导VL通路的整体突触增强。将强直刺激对被动回避任务学习和记忆的影响与切断同一路径的影响进行了比较。强直刺激加速了短期学习，而横断则减慢了避免攻击负强化物体的短期学习。然而，两种处理都损害了第二天的长期记忆。我们的结果表明，章鱼的学习和记忆系统与哺乳动物一样，分为短期和长期记忆位点。在章鱼中，这两个记忆位点并非独立；通过LTP介导长期记忆获取的VL，也调节控制行为和短期学习的回路。
