Gal-Ben-Ari Shunit, Rosenblum Kobi
Department of Neurobiology, University of Haifa Haifa, Israel.
Front Behav Neurosci. 2012 Jan 5;5:87. doi: 10.3389/fnbeh.2011.00087. eCollection 2011.
The senses of taste and odor are both chemical senses. However, whereas an organism can detect an odor at a relatively long distance from its source, taste serves as the ultimate proximate gatekeeper of food intake: it helps in avoiding poisons and consuming beneficial substances. The automatic reaction to a given taste has been developed during evolution and is well adapted to conditions that may occur with high probability during the lifetime of an organism. However, in addition to this automatic reaction, animals can learn and remember tastes, together with their positive or negative values, with high precision and in light of minimal experience. This ability of mammalians to learn and remember tastes has been studied extensively in rodents through application of reasonably simple and well defined behavioral paradigms. The learning process follows a temporal continuum similar to those of other memories: acquisition, consolidation, retrieval, relearning, and reconsolidation. Moreover, inhibiting protein synthesis in the gustatory cortex (GC) specifically affects the consolidation phase of taste memory, i.e., the transformation of short- to long-term memory, in keeping with the general biochemical definition of memory consolidation. This review aims to present a general background of taste learning, and to focus on recent findings regarding the molecular mechanisms underlying taste-memory consolidation in the GC. Specifically, the roles of neurotransmitters, neuromodulators, immediate early genes, and translation regulation are addressed.
味觉和嗅觉都是化学感觉。然而，生物体能够在离气味源相对较远的距离检测到气味，而味觉则是食物摄入的最终直接把关者：它有助于避免摄入毒物并摄取有益物质。对特定味道的自动反应是在进化过程中形成的，并且很好地适应了生物体在其生命周期中很可能出现的情况。然而，除了这种自动反应之外，动物还能够根据极少的经验，高精度地学习并记住味道及其正面或负面价值。通过应用合理简单且定义明确的行为范式，在啮齿动物中对哺乳动物的这种学习和记忆味道的能力进行了广泛研究。学习过程遵循与其他记忆相似的时间连续性：获取、巩固、检索、再学习和再巩固。此外，抑制味觉皮层（GC）中的蛋白质合成会特别影响味觉记忆的巩固阶段，即从短期记忆到长期记忆的转变，这与记忆巩固的一般生化定义相符。本综述旨在介绍味觉学习的一般背景，并聚焦于味觉记忆在GC中巩固的分子机制的最新研究发现。具体而言，将探讨神经递质、神经调质、即早基因和翻译调控的作用。
