An Existential Crisis in Neuroscience • Hacker News Board

Re: An Existential Crisis in Neuroscience

#91

Post by buboard » Sat, Jan 25, 2020, 11:54 PM UTC

monadic2 wrote: post #90

buboard wrote: post #84

Earlier quoted context omitted.

tbf it's debatable if there 's a lot to learn from C.elegans. Simple animals have been studied for decades from aplysia to the mouse. But those are not behaviours that are interesting when attempting to learn more about the human brain. The Allen institute's connectome project is more relevant to mammals, even if it's only a tiny volume of the mouse cortex, in order to mildly constrain models of brain function. Even…

How do you validate your models if you can't validate a simpler one first?

c elegans has very primitive, simple behaviours. It's not really possible to get something useful out of it about either our cognitive functions or our brain disorders. The things that regard single cell pathologies (e.g. plasticity) are already studied in vitro in mammalian cells. There s probably many cognitive phenomena that only become apparent in large brain sizes, so i m not sure this method scales up.

Re: An Existential Crisis in Neuroscience

#92

Post by ggm » Sun, Jan 26, 2020, 12:04 AM UTC

lambdaloop wrote: post #86

ImaTigger wrote: post #75

I am a computational cognitive neuroscientist, an have worked at many levels. I find each kind of data and model useful to some extent, but I have to admit that the least useful, are, to my mind, those at the detailed neural network level, like the ones discussing in this paper. Somewhat more useful are higher level dynamic architecture models, and, at the highest level, cognitive models, which constrain the behavior…

As a counterpoint, I am a computational neuroscientist who transitioned form working in human cognition to fruit fly motor control. Fruit fly neuroscience in the past decade has advanced tremendously. With the latest tools, we can record activity from specific genetically labeled neurons while stimulating others. We have identified specific groups of neurons to stimulate to get the fly to groom, walk, turn, and even…

much simpler by how many orders of magnitude? If it's surface area driven it rises as a function of size more slowly for increases in volume. If it's connectionist then it's an O(n^2) Increase?

Re: An Existential Crisis in Neuroscience

#93

Post by gedy » Sun, Jan 26, 2020, 12:20 AM UTC

lambdaloop wrote: post #86

ImaTigger wrote: post #75

I am a computational cognitive neuroscientist, an have worked at many levels. I find each kind of data and model useful to some extent, but I have to admit that the least useful, are, to my mind, those at the detailed neural network level, like the ones discussing in this paper. Somewhat more useful are higher level dynamic architecture models, and, at the highest level, cognitive models, which constrain the behavior…

As a counterpoint, I am a computational neuroscientist who transitioned form working in human cognition to fruit fly motor control. Fruit fly neuroscience in the past decade has advanced tremendously. With the latest tools, we can record activity from specific genetically labeled neurons while stimulating others. We have identified specific groups of neurons to stimulate to get the fly to groom, walk, turn, and even…

> We have identified specific groups of neurons to stimulate to get the fly to groom, walk, turn, and even walk backwards

This made me realize we may one day willing allow human brain controls to get us to do things we don't want - Work, Exercise, etc.

Re: An Existential Crisis in Neuroscience

#94

Post by Balgair » Sun, Jan 26, 2020, 12:20 AM UTC

garmaine wrote: post #87

Balgair wrote: post #60

Earlier quoted context omitted.

It's that the author is undergoing a 'crisis', not that the field is. The title is clever, not descriptive. More broadly, there is a crisis. Our statistical methods/understandings are not working out in these large N-dimensional data sets, at least for the researchers that were raised on excel and not numpy. Aside: I'm surprised that the FAANGs haven't revolutionized statistics yet. When you have 'phase changes' wher…

> Aside: I'm surprised that the FAANGs haven't revolutionized statistics yet. What does that even mean?

Like, with QM, we had the time and equipment to start pointing radium at some gold foil. We came up with some surprising results. With economics, we finally got enough data in to say that people really are not rational at all. With biology, we finally got the time and equipment to poke audio amplifiers into rabbit brains and some strange stuff happened. Etc.

Similarly, with all this 'big data', I would have guessed that we would have come up with something kinda like that. Finally, we have all this stuff coming in. It's all fairly well captured, fairly well correlated, and fairly valuable so you can pay people to just screw around in the labs and see what drops out.

Re: An Existential Crisis in Neuroscience

#95

Post by Joof » Sun, Jan 26, 2020, 1:10 AM UTC

lambdaloop wrote: post #86

ImaTigger wrote: post #75

I am a computational cognitive neuroscientist, an have worked at many levels. I find each kind of data and model useful to some extent, but I have to admit that the least useful, are, to my mind, those at the detailed neural network level, like the ones discussing in this paper. Somewhat more useful are higher level dynamic architecture models, and, at the highest level, cognitive models, which constrain the behavior…

As a counterpoint, I am a computational neuroscientist who transitioned form working in human cognition to fruit fly motor control. Fruit fly neuroscience in the past decade has advanced tremendously. With the latest tools, we can record activity from specific genetically labeled neurons while stimulating others. We have identified specific groups of neurons to stimulate to get the fly to groom, walk, turn, and even…

The poster above you is why I decided to just work as a software engineer instead. It was such a depressing and bleak field. Thank you for having another opinion!

Re: An Existential Crisis in Neuroscience

#96

Post by dr_dshiv » Sun, Jan 26, 2020, 1:20 AM UTC

ImaTigger wrote: post #81

dr_dshiv wrote: post #77

Earlier quoted context omitted.

Have you read smolensky's harmonium paper? It's the first restricted Boltzmann Machine -- and I believe elman and smolensky were colleagues with hinton back at UCSD (with rumelhart and Don Norman, et al). The approach was focused on presymbolic processing -- and tried to optimize harmony. Harmony was, interestingly, the first mathematical model of the mind (by Pythagoreans/platonists in ancient Greece). It has a lot…

I know about Smolensky's theories (have probably read that paper, but don't remember it exactly; have def. read others by PS); PS and JE are definitely contemporaries, and work/have worked in similar areas. However, these two theories operate at different levels and time scales. The oscillatory coupling theories of PS et al are related to real time computations carried out by neural networks, whereas the trophic wave…

One thing that shocked me was that no one ever tried to connect "cognitive dissonance", one of the most successful social psychology theories of all time, to actual dissonance in neural oscillations.

Consonance results in greater periodicity, meaning that the action potentials are more likely to line up, whereas dissonance has less periodicity, so action potentials don't line up. It feels better (there is pleasure) when the action potentials align because of hebbian reinforcement (synchronous firing). This assumes that reinforcement would be pleasurable, but pleasure is the main reinforcer at a cognitive level.

Re: An Existential Crisis in Neuroscience

#97

Post by 19f191ty » Sun, Jan 26, 2020, 1:33 AM UTC

buboard wrote: post #84

_xerxes_ wrote: post #27

The article touched upon the C. elegans connectome. There are a few interesting projects attempting to simulate the creature. https://en.wikipedia.org/wiki/OpenWorm https://en.wikipedia.org/wiki/WormBase

tbf it's debatable if there 's a lot to learn from C.elegans. Simple animals have been studied for decades from aplysia to the mouse. But those are not behaviours that are interesting when attempting to learn more about the human brain. The Allen institute's connectome project is more relevant to mammals, even if it's only a tiny volume of the mouse cortex, in order to mildly constrain models of brain function. Even…

I don't even know where to begin rebutting your argument. Most of the stuff we actually know, actionable knowledge that has withstood the test of time, comes from small animals, including C. elegans, Drosophila, Aplysia and others. This is because a lot of the stuff is genetically conserved. Even things that are considered specific to mammals, neuromodulatory systems such as dopamine, serotonin are highly conserved. For example worms, flies etc they all get hooked on cocaine through what's thought to be a very similar pathway. Pathways governing such "complex" behaviors as learning, memory, exploration, exploitation etc. all seem highly conserved, which means that a lot can he learned. Source: I'm a worm neuroscientist working on mathematical aspects of neuromodulation of behavior.

Re: An Existential Crisis in Neuroscience

#98

Post by garmaine » Sun, Jan 26, 2020, 1:39 AM UTC

Balgair wrote: post #94

garmaine wrote: post #87

Earlier quoted context omitted.

> Aside: I'm surprised that the FAANGs haven't revolutionized statistics yet. What does that even mean?

Like, with QM, we had the time and equipment to start pointing radium at some gold foil. We came up with some surprising results. With economics, we finally got enough data in to say that people really are not rational at all. With biology, we finally got the time and equipment to poke audio amplifiers into rabbit brains and some strange stuff happened. Etc. Similarly, with all this 'big data', I would have guessed t…

One of those stands out as different from the others: statistics. It's a branch of math. It's fundamental. We've proven its properties to be comprehensive, such that any other formulation with the same basic axioms would do the same thing.

It's not like when we got a lot of experience gathering physical data we suddenly realized we were doing integrals and derivatives wrong.

Re: An Existential Crisis in Neuroscience

#99

Post by Balgair » Sun, Jan 26, 2020, 1:49 AM UTC

garmaine wrote: post #98

Balgair wrote: post #94

Earlier quoted context omitted.

Like, with QM, we had the time and equipment to start pointing radium at some gold foil. We came up with some surprising results. With economics, we finally got enough data in to say that people really are not rational at all. With biology, we finally got the time and equipment to poke audio amplifiers into rabbit brains and some strange stuff happened. Etc. Similarly, with all this 'big data', I would have guessed t…

One of those stands out as different from the others: statistics. It's a branch of math. It's fundamental. We've proven its properties to be comprehensive, such that any other formulation with the same basic axioms would do the same thing. It's not like when we got a lot of experience gathering physical data we suddenly realized we were doing integrals and derivatives wrong.

I mean sort-of?

Math is a brach of logic, sure, but the computer has acted like a microscope for math already. We can more easily check our conjectures and see if they hold true. Also, we've been able to communicate better, so that has helped out math as well. Even though math is 'above' us little humans, the day-to-day work of mathematicians has been helped out a lot, even in the small ways of not having to lug your mortal-coil through the library stacks.

So, with all this big data, I'd have guessed that we could have seen more edge cases with statistics. Little areas where someone said 'huh that's funny'.

Re: An Existential Crisis in Neuroscience

#100

Post by nine_k » Sun, Jan 26, 2020, 3:36 AM UTC

gedy wrote: post #93

lambdaloop wrote: post #86

Earlier quoted context omitted.

As a counterpoint, I am a computational neuroscientist who transitioned form working in human cognition to fruit fly motor control. Fruit fly neuroscience in the past decade has advanced tremendously. With the latest tools, we can record activity from specific genetically labeled neurons while stimulating others. We have identified specific groups of neurons to stimulate to get the fly to groom, walk, turn, and even…

> We have identified specific groups of neurons to stimulate to get the fly to groom, walk, turn, and even walk backwards This made me realize we may one day willing allow human brain controls to get us to do things we don't want - Work, Exercise, etc.

Maybe making human brain actually crave such activities would be even more... valuable.