Effect of Receptive Field on Bitter Taste Coding

最近的行为和神经证据表明，一些苦味刺激可能能够激活离子 在啮齿动物口腔前部的通道，而其他非离子苦味刺激可能是有限的 口腔后部区域的激活。这一系列实验旨在研究 苦味的感觉是由中央味觉系统编码的，特别是关于这种感觉是如何产生的。 信息可能会根据刺激的感受野和苦味的化学结构而改变。 使用的刺激。这将通过记录味觉区单个神经元的动作电位来完成。 孤束核和臂旁核的区域，而刺激更后 感受野（即叶状和轮廓乳头）与各种味觉刺激。虽然 支配这些乳头的舌咽神经对苦味刺激高度敏感，它们的贡献 在CMS水平上的味觉还没有建立。这可能部分是因为， 为了有效地刺激这些受体，需要采取额外的措施，包括缝合和移液管， 领域的还将进行一项心理物理实验，以便在 中枢神经系统水平的反应和清醒动物的苦味感知。这将通过 在用苦味刺激进行行为测试之前切断外周味觉神经， 可以确定由这些神经支配的区域中的味觉感受器细胞的数量。 虽然我们通常认为味道不好的食物是有毒的，但一些富含维生素的食物，如 花椰菜和羽衣甘蓝也被描述为人类受试者尝起来是苦的。如果我们能更好地理解 苦味是如何被味觉系统编码的，也许这个信息可以用来改善 某些药物和/或健康食品的味道。

Recent behavioral and neural evidence suggests that some bitter stimuli may be capable of activating ion channels in the anterior portion of the oral cavity in rodents, while other nonionic bitter stimuli may be limited to activation of the posterior region of the mouth. This series of experiments is designed to examine how the sensation of bitterness is encoded by the central gustatory system, specifically with regard to how this nformation might change depending on the receptive fields stimulated and the chemical structure of bitter stimuli used. This will be accomplished by recording action potentials from single neurons in the gustatory regions of nucleus of the solitary tract and parabrachial nucleus, while stimulating the more posterior receptive fields (i.e. the foliate and circumvallate papillae) with a variety of taste stimuli. Although the glossopharyngeal nerve, which innervates these papillae, is highly sensitive to bitter stimuli, their contribution to taste perception at the level of the CMS has not been established. This may be due in part to the fact that additional measures, including sutures and pipettes, are necessary to effectively stimulate these receptive fields. A psychophysical experiment will also be performed so that parallels can be drawn between responses at the level of the CNS and bitter taste perception in awake animals. This will be accomplished by severing sets of peripheral gustatory nerves prior to behavioral testing with bitter stimuli so that the influence of taste receptor cells in the fields innervated by these nerves can be determined. Although we typically think of bitter-tasting foods as being toxic, a number of vitamin-rich foods, such as broccoli and kale, have also been described as tasting bitter by human subjects. If we can better understand how bitter taste is encoded by the gustatory system, perhaps this information could be used to improve the taste of certain medications and/or healthy foods.