Relating Synaptic Plasticity to Changes in Odor Representation and Perception

嗅觉系统提供了一个独特的强大环境，在其中探索感觉的可塑性 哺乳动物，因为嗅觉系统中最早的中央处理发生在 嗅球，一种在动物模型中可以在体内物理和光学上访问的结构，因为 分子基因技术的最新进展为研究人类基因组学提供了极好的实验工具 这片区域。使用分子遗传学工具和活体光学成像技术的组合，我已经 最近研究表明，嗅觉系统对递质释放具有快速反馈的突触前抑制作用。 来自嗅神经。我假设这个电路的快速可塑性提供了自适应的增益控制 用于从鼻子输入的初级感觉，因此在气味的编码中起主要作用 浓度和对气味强度的感知。此外，初步数据表明，这种抑制作用 电路可能会随着时间的推移而改变，以适应嗅觉环境的变化。这些活动的首要目标是 实验是为了验证这样一种假设，即对初级感觉输入的突触前调制 嗅球参与了气味浓度的编码。这些实验的第二个目的是 使用光学成像技术验证感觉环境变化导致可塑性的假设 在嗅球输入端的气味表示中。这些实验的最终目的是使用 测试这种可塑性如何影响对气味质量和强度的感知的行为分析。

The olfactory system provides a uniquely powerful environment in which to explore sensory plasticity in mammals, because the earliest central processing in the olfactory system takes place in the glomeruli of the olfactory bulb, a structure that is physically and optically accessible in vivo in animal models, and because recent advances in molecular genetic technology have produced excellent experimental tools for studies in this area. Using a combination of molecular genetic tools and in vivo optical imaging techniques, I have recently shown that the olfactory system exhibits rapid feedback presynaptic inhibition of transmitter release from the olfactory nerve. I hypothesize that the rapid plasticity of this circuit provides adaptive gain control for the primary sensory input from the nose, and thus plays a major role in the encoding of odorant concentration and the perception of odor intensity. Moreover, preliminary data suggest that this inhibitory circuitry may change over time to accommodate changes in the olfactory environment. The first aim of these experiments is to test the hypothesis that this presynaptic modulation of primary sensory input to the olfactory bulb contributes to the encoding of odor concentration. The second aim of these experiments is to use optical imaging techniques to test the hypothesis that changes in sensory environment induces plasticity in the representation of odors at the input to the olfactory bulb. The final aim of these experiments is to use behavioral assays to test how this plasticity affects the perception of odor quality and intensity.