[jfries]

This is very interesting.

I remember reading about pilots placing an electrode on the tongue and eventually learning to intuitively feel what the external sensor was telling them.

Or another one about a person wearing a belt which always vibrated in the spot facing north. This helped them navigate cities more efficiently after getting accustomed to the vibrations.

Do you have other examples?

[pygy_]

Anecdotally, I participated, as a non-blind control, to a study assessing cross-modal perception in blind folks (how they use their visual cortex to analyze haptic stimuli).

The meat of the experience was evaluating the performance of pattern recognition on an array of electrode placed on the tongue.

Before and after training, all subjects underwent evoked potential recordings of their tongue (recodring the EEG following electric stimuly on the tongue).

Being aware of the protocol in advance, during the "before" evoked potential session, I concentrated on my mouth, visualizing it as a place I was sitting in.

I ended up experiencing blue phosphenes (light flashes) sinc'ed with the electric pulses, and my visual cortex was lighting up along with my sensory cortex. That was my first and only proper synesthetic experience (I used to associate vowels and colors as a kid, each vowel clearly mapped to a color, but it was conceptual, not perceptual).

Since I was an outlier (similar evoked potentials were only seen in blind subjects after training), I was excluded from the rest of the study, so I could not experience the complex patterns on the "tongue display unit".

https://www.sciencesquared.eu/sites/default/files/toungue_di...

[vkolencik]

This is discussed in the book Incognito by David Eagleman. I remember reading about someone learning to "see" with their tongue. Along the same line, his team developed a vest which translates information into vibration patterns on the torso: https://www.smithsonianmag.com/innovation/could-this-futuris...

[vanderZwan]

> Or another one about a person wearing a belt which always vibrated in the spot facing north. This helped them navigate cities more efficiently after getting accustomed to the vibrations.

IIRC, the participants also felt incredibly lost after they had to give back the belt

[abqader]

This is a strong area of personal interest for me. I think BCI will eventually begin to incorporate those ideas of turning external stimuli such as haptics into representations of data our brain can understand.

ML is popular because it’s a set of learning algorithms that we can feed numeric data and output some learned prediction. Once we learn how to feed this numeric data to the brain (similar to the tongue sensor or a haptic vest), then we have the most efficient learning algorithm consuming and making sense of this data!!

[teekert]

That's so cool, I'd love a wifi belt so that I could sense (all or specific) people coming...

[TeMPOraL]

Those were the exact two I have on my mind. I've actually started building an ankle bracelet for the north-sense to test it out on myself.

People also reported getting a feel for strong EM fields in their surroundings after implanting a small magnet in a finger.

[TheSpiceIsLife]

You might have come across this, or similar, images before (random image search link, no affiliation):

https://www.themystica.com/wp-content/uploads/2018/03/Homunc...

This is a proportional representation of touch-sense nerve density in the skin.

Trade-offs though hey. All the highest density areas are probably also the least convenient location for augmented-synesthesia touch-sense devices.

[ajuc]

I'm pretty sure they missed one spot :)

[TheSpiceIsLife]

Yes, I believe you’re right. That image is very G rated.