This is a special post for quick takes by Tomás B.. Only they can create top-level comments. Comments here also appear on the Quick Takes page and All Posts page.
Inadequate Equilibria lists the example of bright lights to cure SAD. I have a similar idea, though I have no clue if it would work. Can we treat blindness in children by just creating a device that gives children sonar? I think it would be a worthy experiment to create device that makes inaudible cherps and then translates their echos into the audible range and transmits them to some headphones the child wears. Maybe their brains will just figure it out? Alternatively, an audio interface to a lidar or a depth estimation model might do, too.
As I read somewhere in the Internet, even adult people with normal eyesight can learn echolocation. If it's true, obviously blind children can learn it too!