[vankessel]

Tangential but I've always thought it may be possible for a human brain to experience higher spatial dimensions, it's just that all it ever experiences is 3. Imagine a video game is designed in 4 spatial dimensions and is fed directly into the brain through a neuralink type interface. The brain is pretty adaptable, would the recipient correctly experience those 4 dimensions?

[mirimir]

I've seen more than three dimensions with LSD. At least, I've seen what looks a lot like those rotating hypercube images. Except more complicated, and looking somewhat like Mandelbrot sets.

[p1mrx]

Extraordinary claims require extraordinary evidence. With your mind in a suggestible state, it's much easier to convince yourself that you're seeing in 4D than is to actually see in 4D.

[vinceguidry]

It's pretty easy to work out what they actually saw from the words used to describe them. A hypercube rotation is a 4d object projected into 3 dimensions. Nothing extraordinary at all about that.

[mirimir]

Yes, it was a visual hallucination, and so constrained to two dimensions plus perspective. But I clearly recall the sense that I was seeing a 2D projection of a higher-dimensional image.

[p1mrx]

Yeah, visualizing 2D/3D shapes is not extraordinary. "The sense" of an extra dimension is meaningless woo, unless someone with sufficient mathematical experience is able to observe consistent properties of a shape's higher-dimensional structure.

[anon9001]

Obviously anything experiential can be dismissed as "meaningless woo", but as someone who's done a fair amount of LSD and is a lifelong skeptic, it's an unmistakable experience that the hallucinations are taking place in a higher ordered space.

To add a little clarity to what the hallucinations look like, checkout what people describe here: https://psychonautwiki.org/wiki/Geometry

The process of hallucinating on LSD feels like you're sliding a window through a higher dimensional structure projected onto a 2D plane. LSD hallucinations aren't "3D" in the same way that mushroom hallucinations are. LSD feels like infinite 2D planes stacked on top of each other, rather than a 3D, if that makes any sense.

If you pause to meditate and quiet your mind, you can get the hallucinations to briefly stall or at least retain their current character. If you focus on one area and let your mind explore the hallucinating you're looking at and just sort of "let it happen", or perhaps change music/environments/stimulus, you can push the hallucinations in a new direction.

The 2D nature of the hallucinations and the lens-like focusing mechanic does give the impression that you're viewing a projection of a higher dimensional space.

I understand it sounds like woo, but the experience is remarkably similar to the feeling of playing with something like http://4dtoys.com/ and I can very much understand what mirimir is describing.

I don't have any science-based understanding of how the brain works, but maybe I've added enough color that you can understand what the experience feels like.

[numakerg]

It would have to be higher dimensional properties observed by someone who doesn't have mathematical experience relayed to and confirmed by someone who does.

[shawnz]

Visually we perceive 2 dimensions (i.e. you can't see behind things), the third is just something we imagine as being closer to or further from the camera without being able to directly perceive it. So maybe the fourth would be the same, but just orthogonal to the third.

[Izkata]

> the third is just something we imagine as being closer to or further from the camera without being able to directly perceive it.

Er no, we do perceive the third due to having stereoscopic vision.

[infogulch]

You're right that our vision gives us a 3D perception, but only in the same way that a surface in a 3D space may be stretched and squashed and even have discontinuities, but is still fundamentally 2-dimensional, it has no volume. That still doesn't give us volumetric vision.

If you had true 3D/volumetric vision, you would find painting over objects aesthetically pointless, because you see behind not just the paint, but also through every layer and sub-component of the object all at once.

For example, most "3D" video games would seem very strangely empty and hollow to a being that could perceive volumetric space directly, because games are implemented by manipulating (many) fundamentally 2D surfaces in 3D space. This implementation technique works to suspend our disbelief because we don't see 3D volumes, we see 3D surfaces.

I would also be very keen to know if the human brain could directly perceive a volumetric space.

[shawnz]

Stereoscopic vision doesn't let you see a whole 3D scene at once, it just gives some clues as to how far away things are in the 2D scene which you can perceive visually.

[jayd16]

Theres a VR game that let's you explore 4d shapes spatially.

https://store.steampowered.com/app/619210/4D_Toys/

[beefield]

I'd lika to be able to have a vr app that let's me move in 4D space. I guess at least some kind of sensoring for 4D orientation and 4d acceleration should be developed.

[jayd16]

I believe you use the thumb stick for this. It's spatially tracked VR so you only need one more input for the last dimension.

[nothis]

Probably not exactly what you’re talking about but you are aware of the indie game “Miegakure”?

[p1mrx]

There's nothing to be aware of; Miegakure has been vaporware for a decade.

[vankessel]

Ah yeah I remember that from a while back, too bad it isn't out yet.

[buboard]

> it may be possible for a human brain to experience higher spatial dimensions

The visual system has evolved in a 3D world, in vision science actually the human visual system is considered "2.5D". I don't think we can "visualize" higher dimensions even though we can reason and extrapolate about them just fine.

https://en.wikipedia.org/wiki/2.5D_(visual_perception)

[keithnoizu]

I've been wanting to make a vr application for a while that lets you navigate around n dimensional structures with ability to control which dimensions you are moving in.

Also the concept of perceptual extension is interesting, feed in a bunch of additional information and present it in a consistent way until the brain begins to incorporate it in it's world model. e.g. add additional senses.

[vankessel]

That sounds like it would be very interesting. And while we can't extend our senses just yet, we may be able to swap them. I'm very curious if anyone has tried to use a space-filling Hilbert curve to transform vision into audio and let their brain adjust to it like suggested in this video https://youtu.be/3s7h2MHQtxc

[keithnoizu]

Interesting idea. My understanding is that some of the seeing impaired community does use echo location tools to help navigate. There were also some pin grid tests in the past that effectively gave the seeing impaired the ability to see again. Which is one of the things that got me to thinking about interesting ways we could extend our senses.

[agumonkey]

it may project 4 onto 3 or 2, or find ways to extend original structures to handle higher dimensions