Whisking: Development of an 'active touch' system

搅拌：开发一种“主动触摸”系统。神经科学的一个中心目标是了解感觉-运动整合-大脑如何处理信息并使用它来控制动作。这些信息中的大部分都是主动获取的，使用人类手指或啮齿动物胡须等“移动传感器”扫描环境，将物体的空间属性转换为神经活动的时空模式。这种扫描模式是体感运动系统产生的最复杂的运动之一。然而，关于这些模式是如何在开发过程中获得的，我们知之甚少。我们认为，“主动触摸”系统的正常发展取决于在发育过程中，动物自身的动作与这些动作产生的感觉输入之间的联系的发生。我们假设，围产期对这种感觉-运动联系的操纵将选择性地影响依赖于“主动触摸”的行为任务。为了验证这一假设，我们使用啮齿动物的扭动作为“主动触摸”的模型。我们使用围产期注射肉毒杆菌毒素来可逆地阻断动物自身搅拌动作产生的传入，而不影响其他触觉传入来源(搅拌剥夺)。我们使用新生儿视神经切断术来增加对振动输入的依赖(搅拌补充)。在成年动物中，我们检查了对触觉介导的各种行为的治疗效果，以及对皮质触觉神经元感受野组织的影响。这些研究应该会促进我们对躯体感觉运动系统中调节发育可塑性的过程的理解。

Whisking: Development of an "active touch" system. A central goal of neuroscience is understanding sensorimotor integration-how the brain processes information and uses it to control movements. Much of this information is acquired actively, using "mobile sensors" such as the human fingers or the rodent whiskers, which scan the environment, transforming the spatial properties of objects into spatio-temporal patterns of neural activity. Such scanning patterns are among the most complex movements generated by the somatosensorimotor system. However, we have little information about how such patterns are acquired during development. We suggest that the normal development of "active touch" systems is contingent upon the occurrence, during development, of associations between the animal's own movements and the sensory inputs generated by those movements. We hypothesize that perinatal manipulations of such sensorimotor linkages will selectively impact upon behavioral tasks dependent on "active touch". To test the hypothesis we use rodent whisking as a model of "active touch". We use perinatal injections of Botulinum toxin to reversibly block afference generated by the animal's own whisking movements, leaving intact other sources of vibrissal afference (whisking deprivation). We use neonatal optic nerve section to increase dependence upon vibrissal inputs (whisking supplementation). In adult animals, we examine treatment effects upon a variety of vibrissa-mediated behaviors, and upon the receptive field organization of cortical vibrissal neurons. These studies should advance our understanding of processes mediating developmental plasticity in the somatosensorimotor system.