Contextual taste cues modulate olfactory learning in C. elegans by an occasion-setting mechanism
Contextual taste cues modulate olfactory learning in C. elegans by an occasion-setting mechanism
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DOI：
10.1016/j.cub.2004.06.066
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发表时间：
2004-07-27
期刊：
影响因子：
9.2
通讯作者：
van der Kooy, D
中科院分区：
文献类型：
--
作者：
Law, E;Nuttley, WM;van der Kooy, D
在许多联想学习范例中，对上下文的操纵可以影响跨物种的学习和记忆表现[1-3]。使用味觉线索，创造不同的环境中的线虫线虫的嗅觉适应测定，我们现在表明，在这种联想学习范式的性能是敏感的上下文操作，我们调查的机制（S）用于整合的上下文线索学习。一种可能性是，味觉和嗅觉刺激被感知为组合的混合线索，然后动物以与任何其他单一条件刺激（CS）相同的方式与非条件刺激（US）相关联[4]。另一种观点认为，味觉线索只为嗅觉记忆提取定义了适当的语境，而不直接进入初级联想[5]。对基因突变体的分析表明，嗅觉和上下文线索是由不同的初级感觉神经元感知的，动物使用味觉线索来调节嗅觉学习的能力与它们利用这些相同的味觉线索进行适应的能力无关。我们将这些结果解释为记忆设置机制的证据[5]，在该机制中，上下文线索通过以分层方式发挥作用来调节初级巴甫洛夫关联，以定义记忆回忆的适当设置。
Manipulations of context can affect learning and memory performance across species in many associative learning paradigms [1-3]. Using taste cues to create distinct contexts for olfactory adaptation assays in the nematode Caenorhabditis elegans, we now show that performance in this associative learning paradigm is sensitive to context manipulations, and we investigate the mechanism(s) used for the integration of context cues in learning. One possibility is that the taste and olfactory stimuli are perceived as a combined, blended cue that the animals then associate with the unconditioned stimulus (US) in the same manner as with any other unitary conditioned stimuli (CS) [4]. Alternatively, an occasion-setting model suggests that the taste cues only define the appropriate context for olfactory memory retrieval without directly entering into the primary association [5]. Analysis of genetic mutants demonstrated that the olfactory and context cues are sensed by distinct primary sensory neurons and that the animals' ability to use taste cues to modulate olfactory learning is independent from their ability to utilize these same taste cues for adaptation. We interpret these results as evidence for the occasion-setting mechanism [5] in which context cues modulate primary Pavlovian association by functioning in a hierarchical manner to define the appropriate setting for memory recall.