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> 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?

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.

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.

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.

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.

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