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Upgrade to Superhuman Reflexes Without Feeling Like a Robot

Electrical muscle stimulation can speed up human reflexes. But can we use it without giving up control of our bodies?

2 min read
Still image from a video showing reflexes grabbing a pen as its dropped
Image: University of Chicago/Sony

We're used to seeing robots with reflexes that are much faster than anything humans are capable of, but it's not just high-speed actuators that make them so quick. Perception and control systems outperform our own nervous systems and brains, meaning that we can boost our own reaction times by just letting a robot take control of our muscles. It's not very hard to do this—all it takes is electrical muscle stimulation (EMS), which uses electrode pads attached to the skin to gently shock your muscles, causing them to contract.

By adding sensors to an EMS system, physical reaction times can be significantly reduced, since the EMS is able to actuate your muscles much faster than your brain can. Essentially, you'd be a puppet, having surrendered your free will to a computer that can force you to move. This may not be a trade-off that you want to accept, which is why researchers from Sony and the University of Chicago are working on an EMS system that makes your reflexes noticeably faster without completely removing the feeling that you're doing things yourself.

The typical reaction time for a human is about 250 milliseconds—meaning it takes you about a quarter of a second after you see something to physically react to it. But the researchers explain that "our conscious awareness of intention takes a moment to arise, around 200 ms." In other words, it takes you about 200 milliseconds for your brain to turn sensory input into a decision to do something like move a muscle, and then another 50 or so milliseconds for that muscle to actually start moving. The researchers suggest that this 50-ish millisecond gap between intention and action is a window that they can exploit to make humans react more quickly while still feeling like the action they take is under their control.

The video below shows a series of experiments that demonstrate how reflexes can be usefully accelerated without decreasing the sense of control, or agency, that the user experiences. It turns out that an EMS-driven improvement in reflexes of up to 80 milliseconds is possible while still maintaining the user's sense of agency, which is the difference between success and failure in these particular experiments. 

The downside of this method is that it's not generalized, and only works if your objective is aligned with the objective of the system—as long as you're trying to do the same thing that the system is trying to do, it'll work fine. But if you change your mind at the last millisecond, that's too bad, because your muscles are moving anyway. Fundamentally, this research is showing how to manipulate belief, finding a way for people to think that they're in control even when they're really not. Participants in this study told the researchers things like, "I felt some EMS sensation but still I believe I control my finger." Which, of course, they didn’t.

This research is useful because, well, who doesn't want amazing superhuman reflexes? But also because people will be physically interfacing with robots more and more frequently. Whether it's in the workplace or at home, as we get older, robots have the potential to help us stay healthier for longer. And in the near future, when exoskeletons supplant wheelchairs as mobility aids, and the walking is done for us, it'll be nice to still feel like we're in control of our own bodies.

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Are You Ready for Workplace Brain Scanning?

Extracting and using brain data will make workers happier and more productive, backers say

11 min read
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A photo collage showing a man wearing a eeg headset while looking at a computer screen.
Nadia Radic
DarkGray

Get ready: Neurotechnology is coming to the workplace. Neural sensors are now reliable and affordable enough to support commercial pilot projects that extract productivity-enhancing data from workers’ brains. These projects aren’t confined to specialized workplaces; they’re also happening in offices, factories, farms, and airports. The companies and people behind these neurotech devices are certain that they will improve our lives. But there are serious questions about whether work should be organized around certain functions of the brain, rather than the person as a whole.

To be clear, the kind of neurotech that’s currently available is nowhere close to reading minds. Sensors detect electrical activity across different areas of the brain, and the patterns in that activity can be broadly correlated with different feelings or physiological responses, such as stress, focus, or a reaction to external stimuli. These data can be exploited to make workers more efficient—and, proponents of the technology say, to make them happier. Two of the most interesting innovators in this field are the Israel-based startup InnerEye, which aims to give workers superhuman abilities, and Emotiv, a Silicon Valley neurotech company that’s bringing a brain-tracking wearable to office workers, including those working remotely.

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