Today we present the second and final installment of my wide-ranging interview with holographer, former Oculus CTO, and current entrepreneur Mary Lou Jepsen. Part One ran yesterday—so if you missed it, click right here. Otherwise, you can press play on the embedded player, or pull up the transcript—they're below.

Today we open by talking about some astounding work of University of California-Berkeley neuroscientist Jack Gallant—he trained an AI system to infer what test subjects were viewing on a video screen just by watching their brains light up on an MRI. The AI’s inference videos are grainy, but they're often creepily accurate. Jepsen first saw his work several years ago, then presented it at TED as part of a main-stage talk in 2013

fMRI technology was improving at a respectable pace back then—but nothing resembling Moore’s law—so the days of nodding off in an MRI and receiving a 4K-quality video of your dreams upon awakening seemed extremely distant. But if Jepsen actually finagles all she intends, they could be nigh.

The reason is the near-infrared technology she talked about using to whup the MRI industry’s magnetic butt. If she gets anywhere near her targeted resolution, the system should be able to pull truly vivid images from a user’s visual cortex. It starts feeling a bit like a Black Mirror episode as Jepsen and I discuss both the exciting and the spooky potential of the tech.

We then get to the truly speculative stuff. Could near-infrared light be used to excite, or trigger neurons? If so, could some creepy descendant of this technology be used to implant memories or desires into people? This launches us onto a tour of some of the ethical issues this technology will pose, should it come to full fruition.

If you enjoyed my interview with Jepsen, please consider browsing the full archives of the After On podcast on my site. Alternatively, you can find the show in your favorite podcast app simply by searching for “After On.” I’ve posted deep-dive interviews with dozens of world-class thinkers, founders, and scientists—tackling subjects like cryptocurrency, astrophysics, drones, genomics, synthetic biology, neuroscience, consciousness, privacy and government hacking, and more.

Finally, as noted in yesterday’s article, we’ll take a breather next week, then come back during the week of July 9th with a three-installment episode about Fermi’s paradox.

This special edition of the Ars Technicast podcast can be accessed in the following places:

iTunes:

https://itunes.apple.com/us/podcast/the-ars-technicast/id522504024?mt=2 (Might take several hours after publication to appear.)

RSS:

http://arstechnica.libsyn.com/rss

Stitcher

http://www.stitcher.com/podcast/ars-technicast/the-ars-technicast

Libsyn:

http://directory.libsyn.com/shows/view/id/arstechnica