CHANG: Fascinating. OK. So last up, Regina, you have a story about an intervention that could help people with paralysis walk again. Am I clear on this? I mean, it sounds like it's made for a movie.

BARBER: Yes. I love movies. Yes. Yes.

CHANG: (Laughter).

BARBER: Over a decade ago, Gert-Jan Oskam was paralyzed from a cycling accident, and that injury interrupted the communication between his brain and spinal cord. And recently researchers have reconnected them so he can walk again.

CHANG: Wow. OK, so how does this technology work?

BARBER: Yeah. So first, they need to figure out what his brain signals look like when he's thinking about walking. And they interpret that with something called a brain-computer interface. And that's not new technology. That's been around for a while to, like, move cursors on a screen, to control small robots by just thinking.

And in this case, a brain implant decodes Gert-Jan's thoughts. Then those thoughts are sent wirelessly to a wearable processor that looks like a backpack, and it detects his intentions to move and translates these brain signals into electric pulses. These pulses are sent to another implant that stimulates his spinal cord, allowing him to actually make those movements.

CHANG: And all this happens in, like, just split seconds.

BARBER: Yes.

CHANG: Wow. OK, so you've mentioned parts of this have been done before. So what is actually new here?

BARBER: Yeah. So what's new here is how they combine these two known technologies of reading the brain's thoughts and using them to stimulate the spinal cord. That's according to Marco Capogrosso, a spinal cord injury researcher at the University of Pittsburgh. He's not associated with the study, but he is very impressed on how real this walking looks. The patient could even go up and down ramps, navigate obstacles, go upstairs. And in the past, patients have only been able to kind of have these choppy steps, and it was hard for them to move on anything that wasn't flat ground.

CHANG: This is incredible. But wait, this so far has just been tested on this one individual, right? Like, so...

BARBER: Yeah.

CHANG: ...How might this technology be rolled out more widely?

BARBER: So, same answer as the sticker vaccine - Marco says probably about five to seven years. More research has to be done to see who else this can help - like, level of injury, make sure it's safe, and it's pretty expensive right now.

CHANG: So cool.