Multimodal flavor integration and retronasal olfaction in the rat

描述（由申请人提供）：多模态刺激如何整合是神经科学中的一个基本问题。这个问题是特别相关的风味感知，其中同时刺激的触摸，温度，味觉和嗅觉总是发生在摄入。在人类的功能成像研究提供了重要的见解多模态风味整合的神经基础，但不能解决需要更高的分辨率或实验操作的神经活动或风味体验的问题。为了解决这些问题，本项目的目标是建立一个大鼠模型，研究风味整合的神经机制。为了确定大鼠的鼻后嗅觉是否像人类一样发生，第一项研究将采用光学钙成像来测量清醒大鼠口服气味剂相关的各种行为在嗅球中诱发的时空模式。将同时调查后鼻和鼻前气味之间的感知相似性。为了确定是否发生在大鼠的感知风味整合，第二项研究将调查是否条件性气味厌恶推广到tastants，以及是否条件性味觉厌恶推广到气味。它也将被检查是否以前的气味-味道对经验是必要的泛化发生，以及泛化的特异性是否遵循这种学习的味道-气味质量一致性。一个单独的研究将调查气味厌恶的味觉和气味厌恶的味觉增强的风味经验依赖性。为了确定多感觉整合是否发生在嗅球中，第三项研究将评估口腔刺激是否以及如何调节清醒和急性大鼠的光学成像嗅球中的气味反应。刺激质量一致性的重要性，建立通过调节风味的经验，和时间一致性的风味整合也将进行评估。总之，这些研究旨在提供关于使用大鼠模型的风味感知的神经机制的新知识。公共卫生相关性：该项目研究风味感知的神经基础。由于风味在促进食物摄入方面起着核心作用，因此对风味感知的神经机制的研究对于理解导致肥胖、糖尿病和心血管疾病等饮食相关疾病的感官因素至关重要。

Description (provided by applicant): How multimodal stimuli become integrated is a fundamental question in neuroscience. This question is particularly relevant to flavor perception, in which simultaneous stimulation of touch, temperature, taste and olfaction invariably occurs during ingestion. Functional imaging studies in humans have provided important insights into the neural bases of multimodal flavor integration, yet cannot address issues requiring higher resolution or experimental manipulation of neural activity or of flavor experience. To address these limitations, the goal of the present project is to establish a rat model for investigating the neural mechanisms of flavor integration. To determine whether retronasal olfaction occurs in rats as it does in humans, a first study will employ optical calcium imaging to measure spatio-temporal patterns evoked in the olfactory bulb by various behaviors associated with the oral ingestion of odorants by awake rats. The perceptual similarities between retro- and orthonasal odorants will simultaneously be investigated. To determine whether flavor integration occurs perceptually in rats, a second study will investigate whether conditioned odor aversions generalize to tastants, and whether conditioned taste aversions generalize to odorants. It will also be examined whether prior odor-taste pair experience is necessary for generalization to occur and whether the specificity of the generalization follows this learned taste-odor quality congruence. A separate study will investigate the flavor experience-dependence of the potentiation of an odor aversion by taste and of a taste aversion by odor. To determine whether multi-sensory integration occurs in the olfactory bulb, the third study will evaluate whether and how oral stimuli can modulate odor responses in the optically-imaged olfactory bulb of awake and acute rats. The importance of both stimulus quality congruence, as established by modulating flavor experience, and temporal congruence for flavor integration will also be assessed. Together these studies are intended to provide fundamentally new knowledge about the neural mechanisms of flavor perception using a rat model. PUBLIC HEALTH RELEVANCE: This project investigates the neural basis of flavor perception. Because flavor plays a central role in motivating food intake, research on the neural mechanisms of flavor perception is essential for understanding the sensory factors that contribute to eating-related disorders such as obesity, diabetes and cardiovascular disease.