This man with ALS is “the first power user” of a brain implant that lets him speak
This man with ALS is “the first power user” of a brain implant that lets him speak
这位渐冻症（ALS）患者成为了脑机接口的“首位重度用户”，通过植入设备实现“开口说话”
EXECUTIVE SUMMARY Casey Harrell has had a set of electrodes embedded in his brain for almost three years. Harrell, who has amyotrophic lateral sclerosis (ALS) and is paralyzed, first used his brain-computer interface (BCI) to “speak” sentences with the help of a research team in 2023. Since then, Harrell has clocked thousands of hours of use. He can use the device largely independently, once he’s been “plugged in” with the help of a carer. His team has added new features to it, and Harrell also uses it to surf the web and perform his job. 执行摘要 Casey Harrell 的大脑中植入了一组电极，至今已近三年。Harrell 患有肌萎缩侧索硬化症（ALS，俗称“渐冻症”）并处于瘫痪状态。2023 年，在研究团队的帮助下，他首次使用脑机接口（BCI）“说”出了完整的句子。自那时起，Harrell 的设备使用时长已累计数千小时。在护理人员协助完成“插电”连接后，他基本可以独立使用该设备。研究团队为其增加了新功能，Harrell 现在还能利用它上网和处理工作。
“Living with a disease like ALS, you are supposed to have diminished dreams. I do not,” Harrell tells MIT Technology Review. “Any one of these things would be an absolute godsend of improvement. To have all of them, and many, many more, is truly revolutionary.” “患上像 ALS 这样的疾病，人们往往认为梦想会随之破灭。但我没有，”Harrell 告诉《麻省理工科技评论》，“这些功能中的任何一项都是天赐的改善。而能同时拥有所有这些功能，甚至更多，这简直是革命性的。”
Within the first 22.6 months after the device was implanted, Harrell had used it for more than 3,800 hours at home without any researchers present, the team reported today in the journal Nature Medicine. “He’s the first power user of a speech BCI,” says team member Sergey Stavisky, a neuroengineer at the University of California, Davis. 研究团队今日在《自然-医学》（Nature Medicine）期刊上发表报告称，在设备植入后的前 22.6 个月内，Harrell 在没有研究人员在场的情况下，在家中累计使用了超过 3,800 小时。“他是语音脑机接口的首位‘重度用户’（power user），”加州大学戴维斯分校的神经工程师、团队成员 Sergey Stavisky 表示。
Decoding speech 解码语音
Three years ago, Harrell entrusted David Brandman, an associate professor of neurological surgery at the University of California, Davis, and his colleagues with his brain. Harrell, who was 45 at the time, had already been diagnosed with ALS, a degenerative disease that robs people of the use of their muscles. Harrell was dependent on others to control his wheelchair and to dress and feed him. He had difficulty speaking; people struggled to understand what he was saying. 三年前，Harrell 将自己的大脑“托付”给了加州大学戴维斯分校神经外科副教授 David Brandman 及其同事。当时 45 岁的 Harrell 已经被诊断出患有 ALS，这是一种会剥夺患者肌肉控制能力的退行性疾病。Harrell 依赖他人来操控轮椅、穿衣和进食。他说话困难，人们很难听懂他在说什么。
Then Brandman and his colleagues asked if he’d like to trial a brain implant that might help him communicate. “The industry was [on the] cusp of a transformation, and I wanted to be part of it,” says Harrell. He signed up. 随后，Brandman 和他的同事询问他是否愿意尝试一种可能帮助他交流的脑部植入物。“当时这个行业正处于变革的边缘，我想参与其中，”Harrell 说。他报名参加了试验。
In July 2023, during a five-hour operation, doctors implanted four arrays of 64 electrodes each into his brain. Each pair of arrays was wired to a “pedestal” connection point—creating two docking locations on the exterior of his skull to connect the electrodes to a computer. 2023 年 7 月，在一次长达五小时的手术中，医生在他的大脑中植入了四组电极阵列，每组包含 64 个电极。每两组阵列连接到一个“基座”连接点，在颅骨外侧形成了两个对接位置，以便将电极与计算机相连。
The team had long been working on developing algorithms to decode brain activity into speech. Their system works by recording activity from the speech motor cortex—a region of the brain responsible for the movements that allow us to speak. “There are 39 phonemes that make up all the sounds in the [American] English language,” says Nicholas Card, a neuroengineer at UC Davis and member of the team. Mapping neural activity related to producing each of those phonemes can allow the team to create a personalized speech decoder and software that can “speak” those words. “We first go from brain data to phonemes, and then from phonemes to words,” he says. 该团队长期致力于开发将大脑活动解码为语音的算法。他们的系统通过记录言语运动皮层（大脑中负责控制说话动作的区域）的活动来工作。“构成（美式）英语所有发音的音素共有 39 个，”加州大学戴维斯分校的神经工程师、团队成员 Nicholas Card 说。通过绘制与产生这些音素相关的神经活动，团队能够创建个性化的语音解码器和软件，从而“说”出这些词。“我们首先从大脑数据转换到音素，然后再从音素转换到单词，”他说。
They started using the device around a month after the surgery. The team got Harrell’s speech decoder working on the first day, says Card. On that day in August, Harrell used the device to speak with a 50-word vocabulary, and 99.6% of the words were as he’d intended. That vocabulary was later expanded to 125,000 words with 97.5% accuracy. 手术后约一个月，他们开始使用该设备。Card 表示，团队在第一天就让 Harrell 的语音解码器成功运行。在那一天的 8 月，Harrell 使用该设备以 50 个词汇的词库进行交流，准确率高达 99.6%。后来，词库扩展到了 125,000 个单词，准确率仍保持在 97.5%。
At the time, it was unclear how long the device might last. Brain-computer interfaces are still new—not many people have had them implanted for long periods of time. Scar tissue can form around electrodes in a person’s brain, interfering with their ability to pick up neural activity, for example. But that doesn’t seem to be the case for Harrell. 当时，人们尚不清楚该设备能维持多久。脑机接口技术仍处于起步阶段，植入时间较长的案例并不多。例如，大脑电极周围可能会形成疤痕组织，干扰其捕捉神经活动的能力。但这种情况似乎并未在 Harrell 身上发生。
Power user 重度用户
In another advance, Harrell is now able to use the device more independently. In 2023, members of the research team would have to visit Harrell at his home and physically connect and disconnect him from the device on the days he wanted to use it. Not anymore. The team has since automated more of the system—today, Harrell’s care partner can don and doff it for him. “He’ll wake up, get plugged in, and just get going,” says Stavisky. 在另一项进展中，Harrell 现在能够更独立地使用该设备。2023 年，研究团队成员必须在 Harrell 想使用设备的日子里亲自上门，手动为他连接或断开设备。现在情况不同了。团队已经实现了更多系统的自动化——如今，Harrell 的护理伙伴可以为他穿戴和拆卸设备。“他醒来，接上设备，就可以直接开始工作了，”Stavisky 说。
This is important, says Mariska Vansteesel, a BCI researcher at Utrecht Medical Center who was not involved in the trial. “For these technologies to be relevant for patients, we really need to test them in settings in which they will eventually be used … to demonstrate that it has value, that it’s usable, and that it functions well without the constant involvement of a research team,” she says. 未参与此次试验的乌得勒支医学中心 BCI 研究员 Mariska Vansteesel 表示，这一点至关重要。“为了让这些技术对患者真正产生意义，我们必须在它们最终会被使用的环境中进行测试……以证明其价值、可用性，以及在没有研究团队持续介入的情况下也能良好运行，”她说。
The team has also worked to improve the system itself. It is now 99% accurate, says Stavisky. Harrell can also control a cursor—a game changer that enables him to use his personal computer to send text messages and emails, surf the web, and keep up with his job as an environmental activist. 团队还致力于改进系统本身。Stavisky 表示，目前的准确率已达到 99%。Harrell 还可以控制光标——这是一个巨大的突破，使他能够使用个人电脑发送短信和电子邮件、上网，并继续从事他的环保活动工作。
Over the years, the team has updated the system to accommodate specific requests from Harrell. He is now able to switch on a “privacy mode”—when active, any decoded text will be automatically deleted. He can also opt to use a “profanity filter” while he’s talking to his young daughter. “We have been able to add on to the software side of the device … improving the accuracy and adding more bells and whistles to enable me to be more independent when using the device,” says Harrell. “We are making the road as we walk it, or roll it, so to speak.” 多年来，团队不断更新系统以满足 Harrell 的特定需求。他现在可以开启“隐私模式”——激活后，任何解码的文本都会被自动删除。在与年幼的女儿交谈时，他还可以选择使用“脏话过滤器”。“我们能够在设备的软件层面进行扩展……提高了准确性，并增加了更多功能，使我在使用设备时更加独立，”Harrell 说，“我们是在边走边修路，或者说，是边‘滚’边修路。”
Nothing short of revolutionary 堪称革命性
Vansteesel cautions that while the device is working well for Harrell, there’s no guarantee it will work as well, or as long, for other people with ALS. Over the last decade, she has worked with a woman with ALS who used a fully implanted device to communicate using “brain clicks”—cursor clicks made using brain activity. The woman used her BCI for seven years, but it stopped working toward the end of that period, apparently due to brain degeneration. Vansteesel 提醒道，虽然该设备在 Harrell 身上运行良好，但不能保证它对其他 ALS 患者也能同样有效或持久。在过去十年中，她曾与一名使用全植入式设备通过“大脑点击”（利用大脑活动控制光标点击）进行交流的 ALS 患者合作。那名女性使用了七年 BCI，但在该时期末期设备停止了工作，原因显然是大脑退化。
At any rate, not everyone with ALS will be willing to undergo invasive brain surgery, says Jane Huggins, who is developing noninvasive BCIs at the University of Michigan and was not involved in the trial. “Long-term, independent use with efficient and accurate communication is kind of the holy grail.” 无论如何，并非所有 ALS 患者都愿意接受侵入性脑部手术，密歇根大学正在开发非侵入性 BCI 的 Jane Huggins（未参与此次试验）表示，“实现长期、独立、高效且准确的交流，是这一领域的终极目标。”