Sensory pathways for stimulus detection during behavior

描述(申请人提供)：动物，包括人类，使用主动策略探索环境，包括移动他们的传感器(手指，眼睛)。这种行为的一个很好的例子是啮齿类动物的主动搅拌。在主动摇晃的过程中，老鼠以固定的方式移动胡须，与物体接触(主动触摸)，以识别它们并探索环境。一个重要的问题是，大脑中的感觉系统必须通过将与主动触摸相关的神经活动与移动胡须引起的活动区分开来来检测它。胡须通过三叉神经复合体中的初级感觉中继细胞传递这种感觉信息，三叉神经复合体产生两条主要的上行和对侧通路。一种支配丘脑，主要通向前脑的新皮质(三叉神经丘脑)，另一种支配中脑顶盖上丘的深层(三叉顶)。这两条上升通路在探索性按摩过程中检测主动触摸信号中的作用还知之甚少。我们认为，上丘是一种主要的感觉中继器，通过区分运动相关活动和接触相关活动来检测探索行为中的触摸信号。因此，与众所周知的定位新刺激的作用一致，上丘是在主动探索过程中负责检测感觉刺激的感觉回路的重要组成部分。这个项目有三个目标。第一个目标是确定上丘细胞在搅拌、运动和触摸时的反应特性。第二个目标是确定上丘传入在驱动和/或调节甩动反应中的作用。第三个目标是描述动物在探索行为中主动移动胡须并检测与行为相关的感觉刺激时，上丘细胞的活动和反应特性。这个研究项目的长期目标是揭示感觉检测和处理的神经基础，这与许多神经疾病直接相关。

DESCRIPTION (provided by applicant): Animals, including humans, explore the environment using active strategies that involve moving their sensors (fingers, eyes). An excellent example of this type of behavior is active whisking in rodents. During active whisking, rats move their whiskers in stereotyped ways making contact with objects (active touch) to identify them and to explore the environment. An important problem is that sensory systems in the brain must detect the neural activity related to active touch by distinguishing it from the activity caused by moving the whiskers. The whiskers transmit this sensory information through primary sensory relay cells in the trigeminal complex, which produce two major ascending and contralateral pathways. One innervates the thalamus, leading primarily to the neocortex in the forebrain (trigeminothalamic), and the other innervates the deep layers of the superior colliculus in the midbrain tectum (trigeminotectal). The role of these two ascending pathways in the detection of active touch signals during exploratory whisking is poorly understood. We propose that the superior colliculus is a major sensory relay that serves to detect touch signals during exploratory behavior by differentiating movement-related and contact-related activity. Therefore, in agreement with its well-known role in orienting to novel stimuli, the superior colliculus is an essential component of the sensory circuitry responsible for the detection of sensory stimuli during active exploration. There are three goals in this project. The first goal is to determine the response properties of superior colliculus cells during whisking movement and touch. The second goal is to determine the role of superior colliculus afferents in driving and/or modulating the whisking responses. The third goal is to characterize the activity and response properties of superior colliculus cells as animals actively move their whiskers and detect behaviorally relevant sensory stimuli during exploratory behavior. The long term goal of this research project is to reveal the neural substrates of sensory detection and processing, which has direct relevance to many neurological disorders.