Functional significance of parallel sensory pathways in the rat vibrissal system.

描述（由申请人提供）：最近的研究已经证明了大鼠振动（三叉）感觉通路和视觉通路之间的相似性，这可以扩展振动系统作为视觉感觉处理的模型。具体来说，胼胝体和胼胝体外振动通路被比作细小细胞和大细胞视觉通路，而胼胝体旁振动通路在解剖学上与视觉konio-细胞通路相似。这些结果唤起了三叉神经通路类似于三种视觉通路的假设，可能将空间（parvo），时间（magno）和自我运动（konio）信息分离到三个不同的通路中。然而，这一假设是通过一种有争议的刺激技术产生的：人工胡须，这是有争议的，因为它以一种行为学上难以置信的方式激活用于胡须运动的肌肉。因此，显然有必要独立评估这种刺激技术的结果，以进一步验证该提议的中心假设，即三叉神经的三个主要上升通路（颅神经、颅外神经和颅旁神经）编码空间、时间和自我运动信息。与上行视觉通路（parvo、magno和konio）类似，我们假设颅神经通路编码高灵敏度的空间信息，颅外神经通路携带精确的时间信息，而旁神经通路包含参照信息。中心假设将通过完成三个具体目标来检验。目标1：训练老鼠区分自由空气、平墙和弧形墙。目的2：基于须运动和须接触信息的分离，在脑干三叉神经核水平上建立门神经旁和门神经外通路的功能意义。目的3：基于须运动和接触的时空模式，在脑干三叉神经核（Vnuc）水平上建立lemniscal通路的功能意义。该提案概述了利用清醒、有行为的动物的三个主要创新：(1)在受控行为期间首次从Vnuc进行神经记录，(2)从Vnuc的振动部分进行的第二次慢性记录，以及(3)在不受约束的行为期间首次同时测量所有须接触时间。感知强烈地基于神经系统较低层次的感觉和运动处理。了解感知的感觉运动基础可以为扭曲患者感知的病理带来新的治疗方法。这一建议旨在进一步发展振动系统作为感知的感觉运动基础的模型，这可能有助于理解人类的感知缺陷。

DESCRIPTION (provided by applicant): Recent studies have demonstrated similarities between the rat vibrissal (trigeminal) sensory pathways and visual pathways that could expand the vibrissal system as a model for visual sensory processing. Specifically, the lemniscal and extralemniscal vibrissal pathways have been likened to the parvo-cellular and magno-cellular visual pathways and the paralemniscal vibrissal pathway shows anatomical similarity to the visual konio-cellular pathway. These results evoke the hypothesis that the trigeminal pathways are analogs of the three visual pathways, potentially separating spatial (parvo), temporal (magno) and self-movement (konio) information into three distinct pathways. However, this hypothesis arises through a controversial stimulation technique: artificial whisking, which is disputed because it activates muscles used for whisker motion in an ethologically implausible manner. Thus, there is a clear need to independently valuate the results of this stimulation technique to further test this proposal's central hypothesis that the three major trigeminal ascending pathways (lemniscal, extralemniscal and paralemniscal) encode spatial, temporal and self-movement information. In analogy to the ascending visual pathways (parvo, magno and konio), we hypothesize that the lemniscal pathway encodes high acuity spatial information, the extralemniscal pathway carries precise temporal information, and the paralemniscal pathway contains reafferent information. The central hypothesis will be tested through the completion of three specific aims. Aim 1: Train rats to discriminate between free air, a flat wall and a curved wall. Aim 2: Establish the functional significance of the para- and extra-lemniscal pathways at the level of the brainstem trigeminal nuclei based on a separation of whisker motion and whisker contact information. Aim 3: Establish the functional significance of the lemniscal pathway at the level of the brainstem trigeminal nuclei (Vnuc) based on spatiotemporal patterns of whisker motion and contact. This proposal outlines three primary innovations using the awake, behaving animal: (1) the first neural recording from the Vnuc during a controlled behavior, (2) the second chronic recording from the vibrissal portion of the Vnuc ever made, and (3) the first simultaneous measurement of all whisker contact times during unrestrained behaviors. PUBLIC HEALTH RELEVANCE Perception is based strongly on sensory and motor processing at lower levels of the nervous system. Understanding the sensorimotor basis of perception could lead to novel treatments for pathologies that distort a patient's perceptions. This proposal aims to further develop the vibrissal system as a model of the sensorimotor basis of perception, which could be instrumental for understanding of perceptual deficits in humans.