A developmental analysis of contextual fear conditioning
A developmental analysis of contextual fear conditioning
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DOI：
10.1002/(sici)1098-2302(199603)29:2
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发表时间：
1996-03-01
影响因子：
2.2
通讯作者：
Rudy, JW
中科院分区：
文献类型：
--
作者：
Pugh, CR;Rudy, JW
18天和23天大鼠的情景恐惧条件作用在两个训练环境中进行了比较，透明的有机玻璃小室和黑色的有机玻璃小室。根据条件性防御性冰冻反应来衡量，年龄较大的老鼠比年龄较小的老鼠表现出更多的情景恐惧。在这两个年龄段，条件反射(A)在黑室中比在清理室中更强，(B)保留间隔的非单调功能，在即刻和24小时保持间隔中的冻结比在10分钟间隔中的冻结更大，以及(C)在条件作用之前24小时预先暴露于上下文中，在10分钟保持间隔中观察到增强的条件性冻结。其他实验表明，两个年龄段的大鼠都获得了对上下文的视觉和触觉特征的独立表征。这些结果支持了Rudy和Morledge(1994)的假设，即情景恐惧的条件反射是由短期记忆系统和长期记忆系统共同调节的，而对情景恐惧的长期记忆需要对情景表征的巩固。他们挑战了他们的观点，即18天和23天大鼠的长期记忆过程存在质的发育差异。(C)1996年John Wiley&Sons，Inc.
Contextual fear conditioning by 18- and 23-day-old rats was compared in two training contexts, a transparent Plexiglas chamber or a black Plexiglas chamber. As measured by a conditioned defensive freezing response, older rats displayed more contextual fear than younger rats. At both ages conditioning was (a) stronger in the black chamber than in the clear chamber, (b) a nonmonotonic function of retention interval, with freezing being greater at the immediate and 24-hr retention interval than at the 10-min interval, and (c) preexposure to the context 24 hr before conditioning enhanced conditioned freezing observed at the 10-min retention interval. Additional experiments suggest that rats at both ages acquire independent representations of the visual and tactile features of the context. These results support Rudy and Morledge's (1994) hypothesis that contextual fear conditioning is mediated by both a short-term and a long-term memory system and that long-term memory for contextual fear requires the consolidation of a representation of the context. They challenge their view that there is a qualitative developmental difference in long-term memory processes between 18- and 23-day-old rats. (C) 1996 John Wiley & Sons, Inc.