Comment by mjb | Hacker News Reader

Comment by mjb | Hacker News Reader

> But bat sonar, though clearly a form of perception,is not similar in its operation to any sense that we possess, and there is no reason to suppose that it is subjectively like anything we can experience or imagine.

Philosophy aside, bat sonar is different from the senses we possess in an really interesting way. Our eyes have excellent spatial resolution (up/down, left/right), some rough depth resolution (from stereo), and no innate sense of speed. Our brain processes the signal to fake even better spatial resolution, infer more about depth (small vs far away) and more about speed (angle changes, among other things).

Bat sonar is completely different. Spatial resolution is poor. But they have first-class depth and speed information! They don't necessarily know where something is, but know exactly how far away it is, and how fast that distance is changing. One must suppose that their brains synthesize more spatial information from these senses, but that spatial information is still not going to feel reliable.

I'd love to be able to experience that for an hour. To live in this world where distance and speed are primary senses, and cross-range information is much fuzzier. What an incredibly different way to see the world.

Humans unconsciously echolocate. A lot of claims of "blindsight" turned out to be unconscious echolocation (obstructing hearing killed the blindsight.)

> Researchers from the 1940's through the present have found that normal, sighted people can echolocate - that is, detect properties of silent objects by attending to sound reflected from them. We argue that echolocation is a normal part of our perceptual experience and that there is something 'it is like' to echolocate. Furthermore, we argue that people are often grossly mistaken about their experience of echolocation. If so, echolocation provides a counterexample to the view that we cannot be mistaken about our own current phenomenology.

How Well Do We Know Our Own Conscious Experience? The Case of Human Echolocation

https://faculty.ucr.edu/~eschwitz/SchwitzAbs/Echo.htm

Interestingly enough, humans have been able to use echo location, primarily in blind individuals. https://en.m.wikipedia.org/wiki/Human_echolocation

Yeah! As far as I can tell from the research, what's going on there is primarily getting range information from the amplitude of the return (rather than delay or phase like "real" sonar uses). But still, it's very useful our brains are elastic enough to allow us to develop new senses!

The way you put it makes it sound almost like bat sonar is some kind of Fourier transform of vision. Like solving a physics problem by transforming the position space into momentum space. Cool stuff :)

There are video games based on the concept of echolocation, but the ones I know implement it a bit like a pulsing flashlight in a wireframe style scene. Probably not at all how it would feel like.

Maybe attempting a more realistic depiction of echolocation could lead to interesting gameplay. There are already some games interesting games based on lidar.

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