Optimizing microstimulation to restore lost somatosensation

描述（由申请人提供）：神经受损受试者的感觉和运动功能丧失导致毁灭性的生活质量。在过去的十年里，布林机器接口（bmi）的技术水平已经达到了令人印象深刻的发展水平，它可以通过意志控制的神经信号来恢复运动受损个体的运动能力，但实际上所有这些都完全依赖于视觉反馈。然而，这些发展忽视了体感反馈在运动控制中的重要作用。身体感觉的恢复可能是该领域最重要的发展。本文提出的总体目标是设计一种体感假肢来恢复感觉受损受试者的触觉。我们的方法在许多方面都是新颖和重要的。首先，我们将比较刺激在皮层下和在啮齿动物的须-桶系统皮层结构中的效果。我们预计皮层下刺激将受益于更简单的局部信号编码和上游电路提供的自然处理的结合，而皮层结构将受益于相对容易的访问。其次，我们将比较优化后产生初级体感皮层（S1）活动的刺激训练的效果，这些活动与相应的自然驱动活动非常相似，优化后的刺激训练可以最大限度地向皮层传递信息。我们将在完整的和非传入的动物中进行实验，这些动物分别处于唤醒状态、被动状态和主动感知状态。这种新颖的优化方法应该允许动物在很少或没有训练的情况下解释人工刺激，并且很容易概括到新的环境中。虽然该提案解决了现有bmi最重要的局限性之一，即缺乏体感反馈，但它是由坚实的神经工程原理驱动的，这可能对临床应用中的神经刺激和神经调节产生总体影响。

DESCRIPTION (provided by applicant): Lost sensory and motor function in neurologically impaired subjects leads to a devastating quality of life. The state of the art in Brin Machine Interfaces (BMIs), which restore the ability of motor impaired individuals to make movements using volitionally controlled neural signals, has reached an impressive state of development in the past decade, but virtually all rely exclusively on visual feedback. However, these developments overlook the critical importance of somatosensory feedback in motor control. The restoration of somatosensation in BMIs is likely to be the most important development in this field. The overarching goal of the work proposed here is to design a somatosensory prosthesis to restore tactile sensation to sensory impaired subjects. Our approach is novel and significant in a number of respects. First, we will compare the efficac of stimulation in subcortical to that in cortical structures in the rodent's whisker-­--barel system. We expect that subcortical stimulation will benefit from the combination of simpler local signal encoding and the natural processing provided by upstream circuits, while cortical structures will benefit from the relative ease of access. Second, we will compar the efficacy of stimulus trains optimized to produce activity in the primary somatosensory cortex (S1) that closely mimic that of the corresponding naturally driven activity to nes optimized to maximize information transfer to cortex. We will do so in intact and in de-­afferented animals during aroused, passive and active sensing states. This novel optimization approach should allow the animal to interpret the artificial stimulation with little t no training and to generalize readily to novel contexts. While the proposal addresses what is arguably one of the most important limitations of existing BMIs, namely the lack of somatosensory feedback, it is driven by solid neural engineering principles that may have overarching impact on neurostimulation and neuromodulation in clinical applications. The PI offers a potent combination of expertise in engineering and neuroscience, has established track records in BMI research, and is therefore uniquely qualified to carry out the work.