The cutaneous code: breaking down neural patterns and optimal noise

皮肤密码：打破神经模式和最佳噪音

• 批准号: RGPIN-2018-06436
• 负责人: Bent, Leah
• 金额: $ 3.42万
• 依托单位: University of Guelph
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=757136
• 关键词: cutaneous; code; breaking; down; neural

Reduced skin input from the feet causes deficits in the sense of body position (proprioception) and declines in the muscular reflexes that control balance. Efforts to augment skin input have taken on several forms, primarily vibration or electrical stimulation to enhance skin input (stochastic resonance; SR). To date, SR vibration technologies have used a large range of frequencies to target all four of the cutaneous mechanoreceptors that reside in the skin (Slow adapting; SA and Fast Adapting FA, type I and II). However, work in our lab has shown there are stronger reflex connections from specific subclasses of afferents (SA type I and FA type I) to motor neurons of the arms and legs, suggesting these mechanoreceptors may have a larger role in balance control. As a result, it would be more effective to focus SR frequencies to enable targeted receptor activation of these relevant subclasses. The first important step is to identify which receptors are activated during natural movements. In the first Aim of the proposal we will identify the fundamental firing characteristics of skin in response to natural load and shear. This project extends our recent work where we examined individual receptor firing to isolated vibration frequencies, which are components of real input. This previous work aimed to better understand how to best activate individual receptor subclasses. By understanding which receptors respond to natural load we can target these receptors to enhance sensory feedback. The second Aim of the proposal is to generate isolated activation of select mechanoreceptors using streamlined SR. In our previous work we have shown that SA and FA receptors in the foot skin have specific frequency bands to which they are most easily activated. Aim 2 will establish whether refined frequency bands (with limited frequencies) will enable targeted activation of specific receptors. Specialized SR may have the ability to improve balance outcomes by targeting individual skin receptors that are relevant for movement and balance control. Finally, we acknowledge that skin receptors, particularly on the feet, are not activated in isolation during natural movement. We aim to enhance specific receptors in our work, and as such it is necessary to understand how the receptors work together to provide the code. The third Aim will examine the excitatory and inhibitory connections between receptor subclasses to help optimize sensory activation. Together this work will identify specific receptors in the skin that we can target for enhanced sensory feedback. The ability to selectively enhance skin receptors in isolation will enable augmented feedback from receptors that are most relevant for balance control. This work can also contribute to the advancement of current insole technologies, improve the sensory interface for prosthetic users, and contribute to the development of navigation devices (gaming, military).

来自足部的皮肤输入减少会导致身体位置感（本体感觉）的缺陷和控制平衡的肌肉反射的下降。增加皮肤输入的努力已经采取了几种形式，主要是振动或电刺激以增强皮肤输入（随机共振; SR）。到目前为止，SR振动技术已经使用了大范围的频率来针对位于皮肤中的所有四种皮肤机械感受器（慢适应; SA和快适应FA，I型和II型）。然而，我们实验室的工作表明，从特定的传入神经亚类（SA I型和FA I型）到手臂和腿部的运动神经元有更强的反射连接，这表明这些机械感受器可能在平衡控制中发挥更大的作用。因此，集中SR频率以实现这些相关亚类的靶向受体激活将更有效。第一个重要步骤是确定哪些受体在自然运动中被激活。在第一个目标的建议，我们将确定的基本点火特性的皮肤在自然负载和剪切。这个项目扩展了我们最近的工作，我们研究了单独的受体放电到孤立的振动频率，这是真实的输入的组成部分。这项先前的工作旨在更好地了解如何最好地激活单个受体亚类。通过了解哪些受体对自然负荷做出反应，我们可以针对这些受体来增强感觉反馈。该提案的第二个目的是使用流线型SR产生选择机械感受器的孤立激活。在我们以前的工作中，我们已经表明，SA和FA受体在足部皮肤中具有特定的频带，它们最容易被激活。目标2将确定细化的频带（具有有限的频率）是否能够靶向激活特定受体。专门的SR可以具有通过靶向与运动和平衡控制相关的个体皮肤受体来改善平衡结果的能力。最后，我们承认，皮肤受体，特别是在脚上，在自然运动过程中不会孤立地激活。我们的目标是在我们的工作中增强特定的受体，因此有必要了解受体如何共同工作以提供代码。第三个目标将检查受体亚类之间的兴奋性和抑制性连接，以帮助优化感觉激活。这项工作将共同确定皮肤中的特定受体，我们可以针对增强的感觉反馈。选择性地增强孤立的皮肤受体的能力将使得能够增强来自与平衡控制最相关的受体的反馈。这项工作还可以促进当前鞋垫技术的进步，改善假肢用户的感觉界面，并有助于导航设备（游戏，军事）的发展。