A Pilot Clinical Trial for Speech Neuroprosthesis

导致沟通障碍的神经损伤是毁灭性的。这项拟议的试点试验旨在评估语音假体技术在一小部分瘫痪患者中的可行性。我们将利用长达十年的人类言语运动皮质功能特性的科学研究，以及最近在正常说话的患者中植入电极的语音解码演示(用于癫痫手术计划)。我们建议对用于恢复通讯的长期直接神经接口的早期可行性进行研究。为了实现这一目标，我们提出了三个关键创新：1)从整个外侧运动皮质(包括语音运动皮质)采样的长期植入的高密度128通道皮层脑电(ECoG)阵列，2)最先进的神经网络解码方法的应用，以及3)文本和语音合成解码方法的直接比较。皮质脑电图术是一种使用非穿透电极从大脑表面记录神经活动(局部场电位)的方法。我们假设ECoG在临床应用上可能比目前的替代方法(如微电极或头皮EEG)具有明显的优势，因为我们可以实现高密度采样并覆盖整个语言运动皮质。我们之前已经证明，这种规模和覆盖范围对于完整个体的语音解码是必要的，也是足够的。ECOG在人类医学应用(如癫痫和脑机接口)中的长期植入具有越来越好的安全性和可靠性。我们已经降低了FDA IDE和当地IRB批准用于研究的监管障碍。这项研究的主要目标是实现通过文本和从神经信号解码的合成语音进行交流。第二个目标是证明基于ECoG的记录在慢性植入环境中的稳健性和稳定性。这些目标将决定语言神经假体技术在瘫痪患者目标人群中的可行性。

Neurological injury that results in the loss of communication is devastating. This proposed pilot trial is designed to evaluate the feasibility of speech prosthetic technology in a small cohort of paralyzed patients. We will leverage a decade-long scientific investigation of the functional properties of human speech motor cortex, and recent demonstration of speech decoding in normally speaking patients implanted with electrodes (for epilepsy surgery planning). We propose an early feasibility study of a long-term direct neural interface for restoration of communication. We propose three critical innovations to achieve this goal: 1) a chronically implanted high-density 128 channel electrocorticography (ECoG) array which samples from the entire lateral motor cortex (including speech motor cortex), 2) application of state-of-the-art neural network decoding approaches, and 3) direct comparison of text and speech synthesis decoder approaches. Electrocorticography is a method of recording neural activity (local field potentials) from the brain surface using non-penetrating electrodes. We hypothesize that ECoG may have distinct advantages for clinical application over current alternatives (e.g. microelectrode or scalp EEG) given that we can achieve both high-density sampling and cover the entire speech motor cortex. We have previously demonstrated that this scale and coverage is necessary and sufficient to decode speech in intact individuals. ECoG has an increasing well documented safety and reliability profile for long-term implantation in human medical applications such epilepsy and brain computer interfaces. We have already de-risked regulatory hurdles with FDA IDE and local IRB approval for investigational use. The primary goals of the study are to enable communication via text and synthesized speech decoded from neural signals. The secondary goal is to demonstrate the robustness and stability of ECoG-based recordings in the chronic implantation setting. These aims will determine the feasibility of speech neuroprosthetic technology in target population of patients who are paralyzed.