Models of Sensory Coding

描述（由申请人提供）：本提案的目标是使用直接实验方法来测试嗅觉编码的两种模型的预测。一个模型表明，许多低特异性神经元代表每一种气味，另一个模型表明，更少，更具体的嗅觉受体联合收割机结合，以传达有关多个分子特征的信息，以表征每一种气味。低特异性模型预测任何病变对任何气味剂的编码没有影响，而组合模型预测局灶性病变的特定缺陷。为了测试这些预测，我们将确定局灶性嗅球病变对识别，辨别和检测特定气味的影响。为此，我们的实验室一直在研究由大量系统不同的气味剂引起的肾小球活动，并且我们已经表征了联合收割机以形成其独特的焦点表征的反应域。重要的是，我们已经确定了气味对引起肾小球模式的不同，只有一个单一的反应域。这些领域的位置的指导下，我们建议病变的特定领域的局灶性肾小球活动的大鼠，然后我们建议应用行为测试，以揭示其产生的气味感知。这些实验应该有助于我们理解嗅觉神经系统编码复杂刺激的机制。

DESCRIPTION (provided by applicant): The goal of this proposal is to use direct experimental approaches to test the predictions of two models of olfactory coding. One model suggests that many low-specificity neural elements represent each odorant and the other model suggests that fewer, more specific olfactory receptors combine to convey information regarding multiple molecular features to characterize each odorant. The low-specificity model predicts no effect of any lesion on the coding of any odorant, while the combinatorial model predicts specific deficits with focal lesions. To test these predictions, we will determine the effects of focal olfactory bulb lesions on the recognition, discrimination, and detection of specific odorants. To that end, our laboratory has been studying the glomerular activity evoked by a large number of systematically differing odorants and we have characterized the response domains that combine to form their unique focal representations. Importantly, we have identified odorant pairs that evoke glomerular patterns differing only by a single response domain. Guided by the locations of these domains, we propose to lesion specific areas of focal glomerular activity of rats and we then propose to apply behavioral tests to reveal their resulting odor perceptions. These experiments should help us understand the mechanism by which the olfactory nervous system codes complex stimuli.