Affective neuroscience of taste reactivity

描述（由申请人提供）：关于大脑机制如何对自然刺激产生积极的情感反应知之甚少。该项目旨在识别伏隔核外壳中的神经回路，这些神经回路独特地能够引起对食物味道的积极情感反应的增加。目的行为情感反应，基于味觉反应范例（人类婴儿，其他灵长类动物和大鼠的味觉诱发反应[在本研究中]）将被研究，以评估大脑操作对情感反应的影响。神经化学受体身份：我们将确定负责引起对味觉的积极情感反应的延髓核中阿片受体亚型的神经化学身份。我们将选择性的阿片激动剂显微注射到一个区域，我们已经证明吗啡增强了对蔗糖味道的积极情感反应。然后通过显微注射选择性阿片类拮抗剂进行阻断，以确认受体亚型身份。然后将阿片样物质的作用与GABA、DA和谷氨酸神经递质在多巴胺中的作用进行比较。我们期望发现，阿片受体激活起着独特的作用，导致增加积极的情感反应（有助于增加食物摄入）。神经解剖学的身份：我们将确定的神经解剖学边界的兴奋性毒素病变映射和显微注射映射技术相结合的兴奋性毒素网站，导致增加积极的情感反应。根据初步结果，我们预计，尾内侧区域的壳的nuclues nubens将是主要siteration.Circuit的相互作用：最后，我们将研究更大的神经系统，其中nuclues nubens是嵌入式的，特别是传出投射到目标结构的积极情感反应的作用。这将开始阐明产生积极情感反应的神经回路，这可能涉及人类情感障碍，涉及积极情感的特定缺陷。

DESCRIPTION (provided by applicant): Little is known about how brain mechanisms cause positive affective reactions to natural stimuli. This project aims to identify neural circuits in the shell of the nucleus accumbens that are uniquiely capable of causing increased positive affective reactions to the taste of food. Objective behavioral affective reactions, based on the taste reactivity paradigm (taste-elicted reactions of human infants, other primates, and rats [in this study]) will be studied to assess the effect of brain manipulations on affective reactions.Neurochemical receptor identity: We will identify the neurochemical identity of the opioid receptor subtype(s) in nucleus accumbens responsible for causing positive affective reactions to tastes. We will make microinjections of selective opioid agonists into a region of accumbens shell where we've shown morphine enhances positive affective reactions to the taste of sucrose. Then blockade by microinjection selective opioid antagonists will be used to confirm receptor subtype identity. Then opioid effects will be compared to GABA, DA, and glutamate neurotransmitter effects in accumbens. We expect to find that accumbens opioid receptor activation plays a unique role in causing increased positive affective reactions (contributing to increased food intake).Neuroanatomical identity: We will identify the neuroanatomical boundary of the accumbens site that causes increased positive affective reactions with a combination of excitotoxin lesion mapping and microinjection mapping techniques. We expect based on preliminary results that a caudal medial region of the shell of the nuclues accumbens will be the chief site.Circuit interactions: Finally, we will examine the larger neural system in which accumbens is embedded, specifically the role of efferent projections to target structures in positive affective reaction. This will begin to clarify the neural circuits underlying generation of positive affective reactions, which may be involved in human affective disorders that involve specific deficits of positive affect.