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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 th

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 well-known that the trillions of long-range connections mean you can find neurons almost everywhere that will fire in response to place/location stimuli. 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. The brain has some redundancy, but it's such an expensive organ (2% of body weight, but 20% of your energy budget) that I would not bet on such widespread replication if avoidable.

monocasa 9y ago
> 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 components of the older 'lizard brain' (if you'll excuse the issues with that term) have a rather fixed function, but the neocortex evolved overrides to those functions? Like sure, we've got a much better understanding of grid cells and place cells in the hippocampus, but does that mean that there isn't similar information being stored in a different way in the neocortex?
- AndrewKemendo 9y ago
  but the neocortex evolved overrides to those functions? In ideal circumstances that might be true but in fact it's usually the other way around. Kahneman's type 1 and type 2 thinking theory expresses this most succinctly: The key theme of the book is that the human mind has two distinct systems of thought. The first, which Kahneman labels System 1, is fast, reflexive, intuitive and automatic. It is the primitive part of thinking that evolved to allow us to survive in a dangerous world. System 2 is slow, rational and deliberative. It is the part of our thinking that we can consciously “observe” and is used for analysis, logical reasoning and deliberate calculations. System 2 can sometimes act as rational governor, overriding judgements or decisions made by System 1. However, the main takeaway from Kahnemen’s life work is that System 2 can be “lazy”, allowing System 1 to lead us to irrational conclusions.
- KingMob 9y ago
  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 receptive fields (which part of a scene a neuron fires in response to) increase in size as you go up the visual hierarchy. V1 neurons will response to tiny parts of a scene, whereas V4/MT and V5 will response to huge swathes of your vision, indicating they become less location-sensitive. Object-identifying neurons may well respond to the object anywhere in your vision, suggesting they're not location-sensitive at all. I guess Hawkins might argue that it's different neurons in association cortex columns that encode location, but frankly, the argument from biology is poor. There are cortical areas mapped out like this... but I can't imagine why Hawkins thinks this is a governing principle for the whole cerebrum.
  - mercer 9y ago
    Thanks for the elaboration! May I ask why you're a former neuroscientist?
    - KingMob 9y ago
      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.
sebastianmarkow 9y ago
This video gives a little more context: https://youtu.be/fhnMUc36opI https://youtu.be/fhnMUc36opI
MarkMMullin 9y ago
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' ?
- KingMob 9y ago
  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.

monocasa 9y ago

> 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 components of the older 'lizard brain' (if you'll excuse the issues with that term) have a rather fixed function, but the neocortex evolved overrides to those functions? Like sure, we've got a much better understanding of grid cells and place cells in the hippocampus, but does that mean that there isn't similar information being stored in a different way in the neocortex?

AndrewKemendo 9y ago
but the neocortex evolved overrides to those functions? In ideal circumstances that might be true but in fact it's usually the other way around. Kahneman's type 1 and type 2 thinking theory expresses this most succinctly: The key theme of the book is that the human mind has two distinct systems of thought. The first, which Kahneman labels System 1, is fast, reflexive, intuitive and automatic. It is the primitive part of thinking that evolved to allow us to survive in a dangerous world. System 2 is slow, rational and deliberative. It is the part of our thinking that we can consciously “observe” and is used for analysis, logical reasoning and deliberate calculations. System 2 can sometimes act as rational governor, overriding judgements or decisions made by System 1. However, the main takeaway from Kahnemen’s life work is that System 2 can be “lazy”, allowing System 1 to lead us to irrational conclusions.
KingMob 9y ago
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 receptive fields (which part of a scene a neuron fires in response to) increase in size as you go up the visual hierarchy. V1 neurons will response to tiny parts of a scene, whereas V4/MT and V5 will response to huge swathes of your vision, indicating they become less location-sensitive. Object-identifying neurons may well respond to the object anywhere in your vision, suggesting they're not location-sensitive at all. I guess Hawkins might argue that it's different neurons in association cortex columns that encode location, but frankly, the argument from biology is poor. There are cortical areas mapped out like this... but I can't imagine why Hawkins thinks this is a governing principle for the whole cerebrum.
- mercer 9y ago
  Thanks for the elaboration! May I ask why you're a former neuroscientist?
  - KingMob 9y ago
    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.

sebastianmarkow 9y ago

This video gives a little more context: https://youtu.be/fhnMUc36opI https://youtu.be/fhnMUc36opI

MarkMMullin 9y ago

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' ?

KingMob 9y ago
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.