Neuromancer49
@Neuromancer49@midwest.social
- Comment on Biohybrid's Neural Implant Connects to the Brain With Living Neurons 4 weeks ago:
See Alk’s comment above, I touched on medical applications.
As for commercial uses, I see very few. These devices are so invasive, I doubt they could be approved for commercial use.
I think the future of Brain Computer Interfacing lies in Functional Near Infrared Spectroscopy (FNIRS). Basically, it uses the same infrared technology as a pulse oximeter to measure changes in blood flow in your brain. Since it uses light (instead of electricity or magnetism) to measure the brain, it’s resistant to basically all the noise endemic to EEG and MRI. It’s also 100% portable. But, the spatial resolution is pretty low.
HOWEVER, the signals have such high temporal resolution. With a strong enough machine learning algorithm, I wonder if someone could interpret the signal well enough for commercial applications. I saw this first-hand in my PhD - one of our lab techs wrote an algorithm that could read as little as 500ms of data and reasonably predict whether the participant was reading a grammatically simple or complex sentence.
It didn’t get published, sadly, due to lab politics. And, honestly, I don’t have 100% faith in the code he used. But I can’t help but wonder.
- Comment on Biohybrid's Neural Implant Connects to the Brain With Living Neurons 4 weeks ago:
A traditional electrode array needs to be as close to the neurons as possible to collect data. So, straight through the dura and pia mater, into the parenchyma where the cell axons and bodies are hanging out. Usually, they collect local data without getting any long distance information - which is a limiting factor to this technology.
The brain needs widespread areas to work in tandem to get most complicated tasks done. An electrode is great for measuring motor activity because those are pretty localized. But, something like memory and language? Not really possible.
There are electrocorticographic devices (ECoG) that places electrodes over a wide area and can rest on the pia mater, on the surface of the brain. Less invasive, but you still need a craniotomy to place the device. They also have less resolution.
- Comment on Biohybrid's Neural Implant Connects to the Brain With Living Neurons 4 weeks ago:
The most practical medical purpose I’ve seen is as a prosthetic implant for people with brain/spinal cord damage. Battelle in Ohio developed a very successful implant and has since received DARPA funding: battelle.org/…/battelle-led-team-wins-darpa-award…. I think that article over-sells the product a little bit.
The biggest obstacle to invasive brain-computer implants like this one is their longevity. Inevitably, any metal electrode implanted in the brain gets rejected by the immune system of the brain. It’s a well-studied process where a glial scar forms, neurons move away from the implant, and the overall signal of the device decreases. We need advances in biocompatibility before this really becomes revolutionary.
- Comment on Biohybrid's Neural Implant Connects to the Brain With Living Neurons 4 weeks ago:
Fantastic question, like Will_a said, I’ve never seen a device designed for input to the brain like this.
In this particular example, if someone were to compromise the device, even though it’s not able to “fry” their brain with direct electricity, they could overload the input neurons with a ton of stimulus. This would likely break the device because the input neurons would die, and it could possibly cause the user to have a seizure depending on how connected the input was to the users brain.
That does bring to mind devices like the one developed by Battelle, where the device reads brain activity and then outputs to a sleeve or cuff designed to stimulate muscles. The goal of the device is to act as a prosthesis for people with spinal cord injuries. I imagine that device was not connected to the internet in any way, but worst case scenario and a hacker compromises the device, they could cause someone’s muscle to sieze up.
- Comment on Biohybrid's Neural Implant Connects to the Brain With Living Neurons 4 weeks ago:
Agree, fascinating question. To be precise, they used genetically modified neurons (aka optogenetics) to test if the device can deliver a signal into the brain. Optogenetics incorporates neurons modified with light-sensitive channel proteins, so the neuron activates when a precise wavelength of light is “seen” by the special protein. One of the coolest methods in neuroscience, in my opinion.
“To see if the idea works in practice they installed the device in mice, using neurons genetically modified to react to light. Three weeks after implantation, they carried out a series of experiments where they trained the mice to respond whenever a light was shone on the device. The mice were able to detect when this happened, suggesting the light-sensitive neurons had merged with their native brain cells.”
- Comment on Biohybrid's Neural Implant Connects to the Brain With Living Neurons 4 weeks ago:
Oh neat, another brain implant startup. I published in this field. If anyone has questions, I’m happy to answer.
- Comment on Interesting to see how dead the MMO genre has become. Are there still players around? 5 months ago:
Touche, forgot this was PatientGamers. Grim Dawn is basically the same sans MMO. It’s the best ARPG I’ve played like, ever, and it’s due for a huge DLC soon. Goes on sale for very cheap often.
Unlike Last Epoch, it’s more item-focused. Unlike PoE, the items aren’t a total nightmare to optimize…
- Comment on Interesting to see how dead the MMO genre has become. Are there still players around? 5 months ago:
Very interesting - I haven’t hit a single bug during my play.
- Comment on Interesting to see how dead the MMO genre has become. Are there still players around? 5 months ago:
A handful if my PoE friends have picked up Last Epoch which I’ve found to be more approachable. Little less MMO but a very similar game.
- Comment on Do you agree with my unpopular opinion about height in fencing? 5 months ago:
Nah. Fenced epee for a bit in a college club. Height advantage was pretty great. I guess it just depends on the weapon.
- Comment on Outer wilds: at what point should I give up? 6 months ago:
Outer Wilds was the best game I played on PS4. I strongly recommend experiencing it for yourself.
I would say the space ship/0g flight is maybe 30% of the gameplay, and you don’t need to be really excellent at it, thankfully.
- Comment on Academia to Industry 7 months ago:
+1 to all of this. See also: phdcomics.com/comics.php?f=1296
- Comment on Trustafarians: When the Rich Pretend to be Poor 8 months ago:
- Comment on After announcing increased prices, Spotify to Pay Songwriters About $150 Million Less Next Year 8 months ago:
Thanks for the recommendation, I was worried they would be missing some of my artists but they had 99% of my music. Can’t wait to ditch Spotify.
- Comment on Why can't people make ai's by making a neuron sim and then scaling it up with a supercomputer to the point where it has a humans number of neurons and then raise it like a human? 8 months ago:
We’ve got some really good theories, though. Neurons make new connections and prune them over time. We know about two types of ion channels within the synapse - AMPA and NMDA. AMPA channels open within the post-synapse neuron when glutamate is released by the pre-synapse neuron. And the AMPA receptor allows sodium ions into the dell, causing it to activate.
If the post-synapse cell fires for a long enough time, i.e. recieves strong enough input from another cells/enough AMPA receptors open, the NMDA receptor opens and calcium enters the cell. Typically an ion of magnesium keeps it closed. Once opened, it triggers a series of cellular mechanisms that cause the connection between the neurons to get stronger.
This is how Donald Hebb’s theory of learning works. en.wikipedia.org/wiki/Hebbian_theory?wprov=sfla1
Cells that fire together, wire together.
- Comment on Why can't people make ai's by making a neuron sim and then scaling it up with a supercomputer to the point where it has a humans number of neurons and then raise it like a human? 8 months ago:
Actually, neuron-based machine learning models can handle this. The connections between the fake neurons can be modeled as a “strength”, or the probability that activating neuron A leads to activation of neuron B. Advanced learning models just change the strength of these connections. If the probability is zero, that’s a “lost” connection.
Those models don’t have physical connections between neurons, but mathematical/programmed connections. Those are easy to change.
- Comment on Why can't people make ai's by making a neuron sim and then scaling it up with a supercomputer to the point where it has a humans number of neurons and then raise it like a human? 8 months ago:
I’ve been quoting Jordan Peterson for years?! Ahhh fuck.
- Comment on Why can't people make ai's by making a neuron sim and then scaling it up with a supercomputer to the point where it has a humans number of neurons and then raise it like a human? 8 months ago:
Actually, we’ve got some pretty sophisticated models of neurons. en.wikipedia.org/wiki/Blue_Brain_Project?wprov=sf…
See my other comment for an example of how little we truly understand about neurons.
- Comment on Why can't people make ai's by making a neuron sim and then scaling it up with a supercomputer to the point where it has a humans number of neurons and then raise it like a human? 8 months ago:
Even assuming we can model the same number of (simple machine learning model) neurons, it’s the connections that matter. The number of possible connections in the human brain is literally greater than the number of atoms in the universe.
- Comment on Why can't people make ai's by making a neuron sim and then scaling it up with a supercomputer to the point where it has a humans number of neurons and then raise it like a human? 8 months ago:
It’s not a terrible idea by any means. It’s pretty hard to do, though. Check out the Blue Brain Project. en.wikipedia.org/wiki/Blue_Brain_Project?wprov=sf…
- Comment on Why can't people make ai's by making a neuron sim and then scaling it up with a supercomputer to the point where it has a humans number of neurons and then raise it like a human? 8 months ago:
Heck, we barely know how neurons work. Sure, we’ve got the important stuff down like action potentials and ion channels, but there’s all sorts of stuff we don’t fully understand yet. For example, we know the huntingtin protein is critical to neuron growth (maybe for axons?), and we know if the gene has too many mutations it causes Huntington’s disease. But we don’t know why huntingtin is essential, or how it actually effects neuron growth. We just know that cells die without it, or when it is misformed.
Now, take that uncertainty and multiply it by the sheer number of genes and proteins we haven’t fully figured out and baby, you’ve got a stew going.
- Comment on Advice on first 3D printer 11 months ago:
Honestly, I started with an Ender 3 for less than $200 and it’s just fine. You’ll have to calibrate and fight with it for a bit, but once you get it running it’s just fine.
- Comment on The Weekly 'What are you playing?' Discussion 1 year ago:
I continue to feed my X4 addiction. Picked up the DLC during the Thanksgiving sale. I’m on my second play, about 35 hours in. Realized I’ve made a lot of mistakes, but that’s half the fun.