字幕表 動画を再生する 英語字幕をプリント ♪ MUSIC ♪ TOM COSTELLO: Imagine moving a mechanical arm by just thinking about it. Or playing a video game using only your mind. Although it may seem like science fiction, scientists and engineers have been developing this technology for decades: it's called brain-computer interface, or BCI. RAJESH RAO: The field of brain-computer interfaces relies on the ability of the brain to be able to generate certain types of responses that can then be harnessed by computers, to be able to be interpreted by computers. COSTELLO: Doctor Rajesh Rao is a neuroengineer and director of the Center for Sensorimotor Neural Engineering at the University of Washington, and is funded by the National Science Foundation. He is developing safe, non-invasive devices that can connect to the brain to accomplish things like controlling a prosthetic arm, or sending commands to a computer. RAO: Looking at the development of this whole field of brain-computer interfaces is to think of it in terms of studying how the brain controls the body. COSTELLO: Whether it's telling the legs to jump in the air, or activating glands to produce sweat, the body's actions and functions are controlled by neurons. They communicate information to and from the brain and the rest of the nervous system using chemical and electrical signals. RAO: And so they're sending these electrical pulses to each other and eventually to the muscles that are then controlling my body. COSTELLO: Much like how the brain controls muscles, researchers can use new technologies to tap into these signals to control machines. RAO: The understanding of how the brain controls movement led to the development of devices and algorithms - that can be implemented on a computer that recognize these patterns in the activity of brain cells and then correspondingly move an artificial device. COSTELLO: To demonstrate how this technology works, Rao and his team of students use a BCI that allows them to study nonverbal communication. First, the student is fitted with an electroencephalogram or EEG cap, which is a series of electrodes placed on the scalp to record brain signals. COSTELLO: When a question appears on the monitor, the student answers "yes" or "no" by looking at one of the flashing lights, which are blinking at different frequencies. When the subject's eyes focus on one of the response lights, the frequency of that specific light is picked up by the visual cortex in the brain, and measured by the EEG cap. 12 hertz represents a "yes" frequency, while a "no" is at a frequency of 13 hertz. STUDENT: Now you can see it peak here at around 12 hertz because no is for 12 hertz. COSTELLO: The computer interprets this signal and moves the cursor in the direction of the response. Using an EEG cap isn't the only way to measure brain activity. Some BCI's use a method called electrocorticography. It also records brain activity but unlike the EEG cap, it is surgically placed directly on the surface of the brain, providing a clearer signal and more precise information. RAO: For example, they can imagine moving their hand. And we use a computer to extract the patterns that correspond to imagined movement of the hand compared to, for example, not imagining and just resting. COSTELLO: From there, the computer can distinguish the two types of brain activity: imagining movement and not imagining movement, then use that information to enable hand control by mental activity. RAO: Given the right kinds of information and the right kinds of devices that are useful for the animal or for the human, the brain can start to adapt. COSTELLO: With practice, the brain can learn to do something it's never done before, like control a prosthetic it's not familiar with. But the key is to understand how these neural networks communicate between the brain and the body. RAO: If you're able to understand the brain better, then you're also able to build better brain-computer interfaces, because they can use those signals that are responsible for different kinds of movements. COSTELLO: As Rao continues to collaborate with engineers, neuroscientists, and neurosurgeons to develop more BCI devices, he is working toward a future where the brain and technology come together seamlessly. ♪ MUSIC ♪
B1 中級 米 脳とコンピュータのインターフェース - 脳の謎 (Brain-Computer Interface - Mysteries of the Brain) 245 8 Lyh Thomas に公開 2021 年 01 月 14 日 シェア シェア 保存 報告 動画の中の単語