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Brain implants allow paralysed monkeys to walk

nature.com

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Re: Brain implants allow paralysed monkeys to walk

#101

Post by lostlogin »

adityab wrote: post #100
lostlogin wrote: post #93

Earlier quoted context omitted.

EEG and MRI seem an obvious starting place, but use humans not monkeys, and this will give better data.

Computational Neuroscience student here. Research of this nature requires reading the electrical spike trains of small sets of neurons (often even individual cells). EEG will give you a measurement of the combined electric field of every single neuron that is active in the entire brain. You can use multiple electrodes and run machine learning algorithms to get a qualitative measure of a macroscopic chunk of brain act…

The point of my comment was that getting good testing is surely easier on humans than monkeys. Actually going in has to happen at some point - why not do this on humans that have volunteered? Cellular level investigations are obviously important but getting a wire in somewhere is not going to happen at a level this small. It will be image guided surely. X-ray would by my guess and hopefully MR but that obviously has its complexities as MR with additional wires isn't that straight forward. A decent MR DTI can help when you want to know where the fibres go, but as you say, the hardware/software division isn't quite so clear with live things.

Re: Brain implants allow paralysed monkeys to walk

#102

Post by tonyplee »

Balgair wrote: post #62
adrianN wrote: post #31

Earlier quoted context omitted.

Even fruit flies share ~60%, and I guess most people agree that insects are fair game.

Yeast cells are ~25% and we make beer out of them, which is basically making them swim around in their own poop (ethanol) until it kills them.

No wonder the beer taste like ...

Re: Brain implants allow paralysed monkeys to walk

#103

Post by honkhonkpants »

citricsquid wrote: post #67
Benjamin_Dobell wrote: post #27

Earlier quoted context omitted.

I would assume it's because monkeys are more intelligent than the animals we tend to eat; cows, chickens, sheep & pigs. Also, intentionally paralysing a creature, leaving it to live in that condition, and then performing experimental surgery/procedures on it is significantly different than slaughtering it. Whilst I appreciate the scientists mean well, and I do understand how this could benefit humanity; this sort of…

The intelligence argument is nonsense. Pigs are as intelligent as dogs. Describe the treatment of livestock (pigs, chickens, cows) but frame it as something that is happening to dogs and you'll drive hundreds of thousands of outraged meat eaters to signing a petition. The reason is cognitive dissonance, we're taught from the moment we can understand that it's okay to farm animals and very few people ever really think…

It doesn't have anything to do with cognitive dissonance. We allow ourselves to slaughter farm animals because we've benefit their species tremendously. The perpetual existence of domestic animal species is virtually assured. By contrast, we have done nothing for monkeys other than relentlessly destroy their habitats.

Re: Brain implants allow paralysed monkeys to walk

#104

Post by digler999 »

nihonde wrote: post #80
citricsquid wrote: post #67

Earlier quoted context omitted.

The intelligence argument is nonsense. Pigs are as intelligent as dogs. Describe the treatment of livestock (pigs, chickens, cows) but frame it as something that is happening to dogs and you'll drive hundreds of thousands of outraged meat eaters to signing a petition. The reason is cognitive dissonance, we're taught from the moment we can understand that it's okay to farm animals and very few people ever really think…

In that case, why not start with human subjects?

Probably because many treatment options can cause harm. So no researcher wants to take the very real risk of harming another human. If you harm an animal unintentionally, and in the name of trying to do something good, not many people will question it. But if you kill a paralyzed patient, or make him suffer excruciating pain, you're likely going to feel remorse and his family is going to demand an answer.

Re: Brain implants allow paralysed monkeys to walk

#105

Post by Balgair »

jobigoud wrote: post #69
Balgair wrote: post #63

Earlier quoted context omitted.

I'm in neuro, that scenario is centuries away. You'd peobably need a clear skull first with exotic glasses we can't even begin to understand physics-wise today. We don't even know what your brain cells mostly are. Is it 10% neurons and 90% glia, or 50% neurons and 50% glia? What are glia even doing? The only data we really get on them is via stroke studies. Neuro is exciting precisely because there is so little known…

But we don't really need to understand something to create technology leveraging it. And we are just getting started with deep learning. And our computers are extremely slow and have tiny storage compared to what they will be.

Ok, I have this pill/wire-probe/exercise-machine, I don't really know what it does, but in some folks it seems to make them happier/healthier, that is all the info you are going to get about said thingy.

Do you use it?

Bio is like that. We really don't know what is going on with a body most of the time. When we try to leverage it, it gives totally nutto results. Like, yeah, water is good for you! Like, maybe we should make it inhale-able! Or yeah, caffeine is alright, makes you wake-up! You should just take NoDoz and never sleep again!

Those are absurd examples, but I hope they illustrate that in bio, 'leveraging' something typically means you are gonna die either real soon or you are gonna get cancer. Fen-phen is a great example of 'leveraging' something in bio [0]. Yeah, you loose weight, but then you blow your heart valves out and end up as worm food.

So when you say that we can just throw computers at the problem, you make a huge mistake with that idea. Your input data is everything. You have to run a LOT of experiments in the real world to get the right data, not just noise you think is data. Living things are really good at staying alive until they aren't. They are not just noisy, they are also altering the experiment along with the experimenter. Homeostasis is a real thing and bodies and living things try to stay happy, healthy, and alive. Like, here is the thing, your experimental test-bed is alive and thinking and is, in some cases, trying to experiment-on/kill-you right back. Try feeding that into a computer! You have 300k+ dependent variables (that you know of) and 10 equations (if you trust those other authors). You are trying to find the mean of N interacting Poisson/Gaussian data sets (you hope they are normal) in N dimensional space and you know that you don't know all the variables and you can only do this on 5 rats.

[0] https://en.wikipedia.org/wiki/Fenfluramine/phentermine

Re: Brain implants allow paralysed monkeys to walk

#106

Post by adityab »

lostlogin wrote: post #101
adityab wrote: post #100

Earlier quoted context omitted.

Computational Neuroscience student here. Research of this nature requires reading the electrical spike trains of small sets of neurons (often even individual cells). EEG will give you a measurement of the combined electric field of every single neuron that is active in the entire brain. You can use multiple electrodes and run machine learning algorithms to get a qualitative measure of a macroscopic chunk of brain act…

The point of my comment was that getting good testing is surely easier on humans than monkeys. Actually going in has to happen at some point - why not do this on humans that have volunteered? Cellular level investigations are obviously important but getting a wire in somewhere is not going to happen at a level this small. It will be image guided surely. X-ray would by my guess and hopefully MR but that obviously has…

The point of my comment was that getting good testing is surely easier on humans than monkeys. Actually going in has to happen at some point - why not do this on humans that have volunteered?

1. Humans do volunteer and it does happen, but even with full consent, regulations will always be stricter on human experimentation than on animals.

2. We don't understand the brain very well and it is easy to make mistakes when working with neural tissue. The consequences of causing irreversible damage/death are much higher when the brain belongs to a human being. On the other hand, most people eat animals for pleasure.

Cellular level investigations are obviously important but getting a wire in somewhere is not going to happen at a level this small

It does happen, there exist small electrode array implants that can be placed in neural tissue to both induce (for example, cause sensations that one can feel) and read-out activity. Such implants are in fact used in some human subjects (there are issues such as development of scar-tissue however).

A decent MR DTI can help when you want to know where the fibres go, but as you say, the hardware/software division isn't quite so clear with live things.

Yeah, for neural interfacing a connectome is not enough, you need to work at the neural code level. Reading out each spike with full spatial resolution from a distance will probably never happen.

Believe me, neuroscientists do not enjoy the fact that invasive experimentation has to be performed on blameless animals; unfortunately it has to be done, unless people are willing to live with the level of understanding/treatments we have now and never move forward.

Re: Brain implants allow paralysed monkeys to walk

#107

Post by Cpoll »

Benjamin_Dobell wrote: post #27
biofox wrote: post #7

"For more than a decade, neuroscientist Grégoire Courtine has been flying every few months from his lab at the Swiss Federal Institute of Technology in Lausanne to another lab in Beijing, China, where he conducts research on monkeys with the aim of treating spinal-cord injuries. The commute is exhausting — on occasion he has even flown to Beijing, done experiments, and returned the same night. But it is worth it, say…

I would assume it's because monkeys are more intelligent than the animals we tend to eat; cows, chickens, sheep & pigs. Also, intentionally paralysing a creature, leaving it to live in that condition, and then performing experimental surgery/procedures on it is significantly different than slaughtering it. Whilst I appreciate the scientists mean well, and I do understand how this could benefit humanity; this sort of…

> Also, intentionally paralysing a creature, leaving it to live in that condition, and then performing experimental surgery/procedures on it is significantly different than slaughtering it.

It seems very similar to intentionally placing an animal in a cage it can't move around in and leaving it to live in that condition. The conditions are, as I understand it, more cruel and unusual than "experimental surgery/procedures."

Re: Brain implants allow paralysed monkeys to walk

#108

Post by kbenson »

citricsquid wrote: post #67
Benjamin_Dobell wrote: post #27

Earlier quoted context omitted.

I would assume it's because monkeys are more intelligent than the animals we tend to eat; cows, chickens, sheep & pigs. Also, intentionally paralysing a creature, leaving it to live in that condition, and then performing experimental surgery/procedures on it is significantly different than slaughtering it. Whilst I appreciate the scientists mean well, and I do understand how this could benefit humanity; this sort of…

The intelligence argument is nonsense. Pigs are as intelligent as dogs. Describe the treatment of livestock (pigs, chickens, cows) but frame it as something that is happening to dogs and you'll drive hundreds of thousands of outraged meat eaters to signing a petition. The reason is cognitive dissonance, we're taught from the moment we can understand that it's okay to farm animals and very few people ever really think…

> To be humane means "having or showing compassion or benevolence" which is about as far from how you can describe the treatment of livestock that you can get.

The problem I have with this is that like in so many other subjects, a too general term has been used to describe a specific type of practice. Traditional farming is very different than factory farming (which seems to be what you are describing), and there are many levels between them. You may still have problems with how a traditional farm is run, and that's fine, you can present those. But presenting features of factory farming as problems with "livestock farming" implies that all livestock farming is like that, and that's untrue.

If you believe all livestock farming is immoral, please use, or at least add justification for the cases where it's not factory farming if you are going to call out all livestock farming. If you are instead specifically targeting factory farming, please endeavor to accurately label it.

Re: Brain implants allow paralysed monkeys to walk

#109

Post by lostlogin »

adityab wrote: post #106
lostlogin wrote: post #101

Earlier quoted context omitted.

The point of my comment was that getting good testing is surely easier on humans than monkeys. Actually going in has to happen at some point - why not do this on humans that have volunteered? Cellular level investigations are obviously important but getting a wire in somewhere is not going to happen at a level this small. It will be image guided surely. X-ray would by my guess and hopefully MR but that obviously has…

The point of my comment was that getting good testing is surely easier on humans than monkeys. Actually going in has to happen at some point - why not do this on humans that have volunteered? 1. Humans do volunteer and it does happen, but even with full consent, regulations will always be stricter on human experimentation than on animals. 2. We don't understand the brain very well and it is easy to make mistakes when…

I think you may misunderstand me as I wasn't clear

"Cellular level investigations are obviously important but getting a wire in somewhere is not going to happen at a level this small It does happen, there exist small electrode array implants that can be placed in neural tissue to both induce (for example, cause sensations that one can feel) and read-out activity. Such implants are in fact used in some human subjects (there are issues such as development of scar-tissue however)."

What I mean - in a human subject the placement of any implant is not going to be guided by anything approaching a cellular level of imaging resolution. It will mostly use conventional radiological image guidance to get close and then measure electrical signals once close. Or is this in fact what you are saying?

Sorry about my formatting - phone.

Re: Brain implants allow paralysed monkeys to walk

#110

Post by Balgair »

sandworm101 wrote: post #65
Balgair wrote: post #58

Earlier quoted context omitted.

Gliosis is a big problem for sure, and the central nervous system's scarring is not well understood at this time. Typically with recording electrodes you can either 'jiggle' them to shake off the scarring cells or pass a small amount of current between the combined electrodes to kill off the cells. These recording electrodes are typically only a few microns apart, so long range damage is a non-issue if the subject is…

The process of refreshing an electrode sounds tortuous for the subject. And your information re monkeys clawing out devices Jurassic Park-style is equally disturbing. This points to the conclusion that the efforts spent internalizing the system has less to do with benefit and more to do with preventing the animal from ending the agony. But speaking of the electrodes, how long do they last in human subjects? Docs have…

Well, there are no pain neurons inside of the central nervous system, so they literally cannot feel anything when you record or 'clean' the tips of the electrodes. Besides, since electricity takes the least impediant path, the current can only flow locally, i.e. over the non-sensing scarring cells. There is not harm to the subject, only to the scar tissue.

Human electrodes can last a lifetime if they are properly done. Look at a pace-maker. They last decades. Granted they are not for individual neuron recordings, but they work great. The first deep brain stimulation patients are about 5 years old now and they seem to be doing fine as a whole, the Parkinson's disease symptoms are significantly lessened and their quality of life is very improved. It'll take more time and effort, but yeah, I think we can overcome the gliosis, though it is probably gong to be a drug interaction with the mechanical/electrical that will do it, not just electrical alone.

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