Active Touch: Vibrissal Tactile Discrimination in the Rat

感官输入通常可以通过特定的行为来增强， 看、听、嗅或感觉。 啮齿动物有很大的 面部胡须，触须，用来调查 触摸物体。 的解剖生理学研究 啮齿动物触须系统已经研究了两者的细胞机制 感觉统合和经验的作用 发展，特别是与躯体感觉皮层有关 大脑。 触须本身的感觉能力 通常从胡须后观察到的总赤字推断 去除，但很少有人知道如何以及这些头发可以 检测或辨别各种自然刺激。 这个项目使用了一种新的方法来确定触须是如何 在行为中被用来制造复杂的触觉 歧视。 被蒙上眼睛的动物将被训练成 区分校准粗糙度的表面;有 有证据表明，啮齿动物可以区分触须， 至少和灵长类动物用指尖一样好。 视频分析 将量化振幅、频率、速度以及 胡须运动和头部运动。 感觉输入的作用 在开发过程中，将通过修剪成排的晶须进行测试， 新生大鼠，直到他们是45日龄，然后允许胡须 增长 已知这种操作会在 大脑的躯体感觉皮层， 成年人的歧视缺陷。 行为策略 将在正常动物和剥夺生殖器官的动物之间进行比较， 看看胡须的运动是如何用来区分的， 是否学会了新的策略。 最后，胡须会 当它们与表面相互作用时， 搅拌模式将与激发时间进行比较 以及在躯体感觉皮层的神经细胞中观察到的抑制。 这些新的研究将填补我们知识上的一个关键空白 将大脑功能与触觉行为联系起来;结果将有一个 不仅对体感科学，而且对感官 科学和神经生物学，以及学习和 行为

Sensory input often can be enhanced by specific behaviors for looking, listening, sniffing or feeling. Rodents have large facial whiskers, the vibrissae, that are used to investigate objects by touch. Studies on anatomy and physiology of the rodent vibrissal system have examined cellular mechanisms of both sensory integration and the role of experience during development, particularly in relation to the somatosensory cortex of the brain. Sensory capabilities of the vibrissae themselves usually have been inferred from gross deficits seen after whisker removal, but little is known about how well these hairs can detect or discriminate various natural stimuli. This project uses a novel approach to determine how the vibrissae are used in behavior to make sophisticated tactile discriminations. Blindfolded animals will be trained to distinguish between surfaces of calibrated roughness; there is evidence that the rodents can discriminate with vibrissae at least as well as primates using fingertips. Video-based analysis will quantify amplitude, frequency, speed, and relations of whisker movements and head movements. The role of sensory input during development will be tested by trimming rows of whiskers of neonatal rats until they are 45 days old, then allowing whisker growth. This manipulation is known to produce abnormalities in the somatosensory cortex of the brain, and expected to produce discrimination deficits in the adults. Behavioral strategies will be compared between normal and neonatally deprived animals, to see how whisker movements are used to discriminate, and whether new strategies are learned. Finally, the whiskers will be studied as they interact with the surface, and the time patterns of whisking will be compared to the timing of excitation and inhibition seen in nerve cells in the somatosensory cortex. These novel studies will fill a critical gap in our knowledge relating brain function to tactile behavior; results will have a high impact not only on somatosensory science, but on sensory science and neurobiology, and on studies of learning and behavior.