Why Does the Neocortex Have Layers and Columns, Learning the World's 3D Structure • Hacker News Board

Re: Why Does the Neocortex Have Layers and Columns, Learning the World's 3D Structure

#31

Post by mercer » Tue, Jul 25, 2017, 2:12 PM UTC

KingMob wrote: post #16

monocasa wrote: post #11

Earlier quoted context omitted.

> On the other hand, the entire medical history of restricted lesions and targeted deficits (Broca's area, Wernicke's area, patient HM's hippocampal anterograde amnesia, visual scotomas, etc etc etc) indicate some brain areas really are specialized for some things more than others. Wouldn't the evolutionary history of the brain imply that information is encoded in two different ways in a lot of cases. Ie. that the co…

In some ways that's true, though the more recent areas tend to cooperate/elaborate, not replace. E.g., both the superior colliculus in the midbrain and the frontal eye fields in neocortex are responsible for making eye movements, but the FEF doesn't override the SC. Even in this case, it's not like eye gaze/movement info is dispersed throughout all the cortex, it's limited to a short list. We also know that the recep…

Thanks for the elaboration! May I ask why you're a former neuroscientist?

Re: Why Does the Neocortex Have Layers and Columns, Learning the World's 3D Structure

#32

Post by MarkMMullin » Wed, Jul 26, 2017, 2:43 PM UTC

amelius wrote: post #10

bmcooley wrote: post #2

Question from someone who is not knowledgeable in ML or AI: Do current implementations of ANNs allow trying out these different types of organizations/structures? Is the structure and workings of neurons sufficiently similar to ANNs that the architecture transfers, or are there huge differences that make understanding and development orthogonal?

And another question on top of that: is there any biological theory that corresponds to backpropagation?

I once attended some talk or other and that question came up - the answer given was flippant, but I always thought it was oddly perceptive...... "Dreaming"

Re: Why Does the Neocortex Have Layers and Columns, Learning the World's 3D Structure

#33

Post by MarkMMullin » Wed, Jul 26, 2017, 2:46 PM UTC

KingMob wrote: post #8

Former neuroscientist here. I have no idea why this paper is at the top of HN, other than that the former founder of Palm is the lead author. Setting aside that it hasn't been published or accepted, the only remotely novel thing seems to be they suggest that location information is represented in each column, and this occurs everywhere in the neocortex. Well, what does the actual biology do? On the one hand, it's wel…

Question - do you see any potential that horizontal versus vertical (with respect to system, not just euclidian space) has to do with cognitive stacking ? For example, is it low level feature detectors in initial visual processing that cause us to jump because they fire a 'snake' stimuli and then higher levels of the cognitive stack catch up and fire 'sorry, my bad' ?

Re: Why Does the Neocortex Have Layers and Columns, Learning the World's 3D Structure

#34

Post by KingMob » Sat, Aug 05, 2017, 5:34 PM UTC

mercer wrote: post #31

KingMob wrote: post #16

Earlier quoted context omitted.

In some ways that's true, though the more recent areas tend to cooperate/elaborate, not replace. E.g., both the superior colliculus in the midbrain and the frontal eye fields in neocortex are responsible for making eye movements, but the FEF doesn't override the SC. Even in this case, it's not like eye gaze/movement info is dispersed throughout all the cortex, it's limited to a short list. We also know that the recep…

Thanks for the elaboration! May I ask why you're a former neuroscientist?

Biology is messy. My data weren't so hot. I didn't want to live in small college towns at the time. Had more fun writing Clojure side projects.

Many, many reasons.

Re: Why Does the Neocortex Have Layers and Columns, Learning the World's 3D Structure

#35

Post by KingMob » Sat, Aug 05, 2017, 7:29 PM UTC

etiam wrote: post #15

KingMob wrote: post #9

Earlier quoted context omitted.

As a former neuroscientist, the majority of people who claim to have grand unified theories of the brain are those who haven't studied it enough to know how far we still have to go.

Well, Hawkins isn't one of them. neuronexmachina's flippant comment misrepresents Hawkins and On Intelligence , which lays out in popular form a scientific theory of neocortical function, with perfectly sane perspective on what that means in the context of the whole brain, due references to neuroscience, suggestions for experimental tests and obvious awareness that the theory may prove wrong or incomplete. I'm distur…

Let me clarify. I'm not just a former neuroscientist; my field was consciousness and perception. Rightly or wrongly (as you may believe), nobody in the field is reading Hawkins.

What we do see a lot of, are people getting enamored of consciousness and dipping their toes in. For all I know Hawkins is an unheard-of genius, but his stuff reads like many of the dilettantes I've already seen.

Re: Why Does the Neocortex Have Layers and Columns, Learning the World's 3D Structure

#36

Post by KingMob » Sat, Aug 05, 2017, 7:37 PM UTC

sebastianmarkow wrote: post #28

KingMob wrote: post #9

Earlier quoted context omitted.

As a former neuroscientist, the majority of people who claim to have grand unified theories of the brain are those who haven't studied it enough to know how far we still have to go.

Hawkings was the PI at the Redwood Neuroscience Institute. Which is now part of Berkeley. He is not an outsider (15+ years of research). You could argue though, that Numenta is more focused on bringing these methods to market, then solely doing research. I get that this doesn't always resonate well with people in academia.

Are you sure he was actually a PI, and not just a funder? According to their list of publications (http://redwood.berkeley.edu/wiki/Publications), Hawkins is not an author on any of them. He's also not listed on the "People" page (http://redwood.berkeley.edu/wiki/People_at_the_Redwood_Cente...), even as an alumnus.

Re: Why Does the Neocortex Have Layers and Columns, Learning the World's 3D Structure

#37

Post by KingMob » Sat, Aug 05, 2017, 7:40 PM UTC

MarkMMullin wrote: post #33

KingMob wrote: post #8

Former neuroscientist here. I have no idea why this paper is at the top of HN, other than that the former founder of Palm is the lead author. Setting aside that it hasn't been published or accepted, the only remotely novel thing seems to be they suggest that location information is represented in each column, and this occurs everywhere in the neocortex. Well, what does the actual biology do? On the one hand, it's wel…

Question - do you see any potential that horizontal versus vertical (with respect to system, not just euclidian space) has to do with cognitive stacking ? For example, is it low level feature detectors in initial visual processing that cause us to jump because they fire a 'snake' stimuli and then higher levels of the cognitive stack catch up and fire 'sorry, my bad' ?

Maybe. I don't know as much about cortical layer differences, but stuff like you describe (fast threat processing) tends to use different, faster pathways through the brain.

Intuitively, this makes sense, because the connection time between two different layers in the same brain tissue is miniscule, but the connection time between different brain regions is much larger, and is therefore likely to dominate overall response time.