This is TFUS [1] with a novel target.

It looks like independent hackers with a strong technical background and little regard for decorum.

Their methodology seems reasonable, and their results are plausible.

I’m reserved about the final part of the post where they moot about applications, but the core result seems solid. They elicited osmosphenes like one can elicit phosphènes by targeting the visual cortex.

1. https://en.wikipedia.org/wiki/Transcranial_focused_ultrasoun...