Cortical processing of olfactory stimuli

感觉信息的大脑皮层处理在感觉辨别、物体识别中起着关键作用 识别和记忆。大脑皮层的感觉处理已经被证明是高度动态的， 过去的经历、当前的背景和期望塑造了人们对世界的看法 以瞬间为基础。感觉加工障碍是损伤的主要组成部分 由中枢神经系统疾病和衰老以及自闭症等先天性疾病引起。在嗅觉中 系统，气味分子和混合物的特征被认为是由一个大家族提取的 受体膜上的嗅觉受体蛋白，并进一步通过突触处理与 嗅球。目前的嗅觉功能理论表明，这些特征重新组装成 知觉气味的整体很大程度上是由初级嗅觉皮质的回路执行的。工作 在本奖项的上一个资助期内完成的工作提供了证据，证明接受该奖项的领域 嗅皮层神经元的(RF)是高度动态的，似乎与 为这一皮质提出的合成角色。也就是说，单个梨状皮质神经元表现出较高的 分子上相似气味的辨别程度，而它们的初级传入、二尖瓣/丛生 细胞似乎表达了检测RF的特征。然而，考虑到广泛的气味和 动物可以辨别的气味混合物，皮质合成编码不太可能是由于 与生俱来的硬连接，而是反映了一种依赖经验的感性学习过程 允许合成新的共生特征。使用多学科方法，目前 Proposal寻求梨状皮质合成编码的进一步证据(目标1)，并开始 探索知觉学习和形成的必要条件和机制 合成皮质射频(目标2和3)。

Cortical processing of sensory information plays a critical role in sensory discrimination, object recognition and memory. Cortical sensory processing has been shown to be highly dynamic, with past experience, current context and expectations shaping how the world is perceived on a moment by moment basis. Disorders of sensory processing constitute a major component of impairments induced by CNS disease and aging, as well as congenital disorders such as autism. In the olfactory system, features of odorant molecules and mixtures are believed to be extracted by a large family of olfactory receptor proteins at the receptor sheet, and further defined by synaptic processing with the olfactory bulb. Current theories of olfactory function suggest that re-assembly of these features into perceptual odorant wholes is performed largely by circuits in the primary olfactory cortex. Work completed during the past funding period of this award provided evidence that receptive fields (RF's) of olfactory cortical neurons were highly dynamic, and appeared to be consistent with the synthetic role proposed for this cortex. Namely, single piriform cortex neurons showed a high degree of discrimination of molecularly similar odorants, whereas their primary afferent, mitral/tufted cells appeared to express feature detecting RF's. However, given the broad range of odorants and odorant mixtures that animals can discriminate, it is unlikely that cortical synthetic coding is due to innate hard-wiring, but rather reflects an experience-dependent, perceptual learning process that allows synthesis of novel co-occurring features. Using a multidisciplinary approach, the present proposal seeks further evidence of synthetic coding in the piriform cortex (Aim 1), and begins to explore the necessary conditions for, and mechanisms of, perceptual learning and formation of synthetic cortical RF's (Aims 2 & 3).