>>42
The difference is, unlike most cortical region matter, it is specialized.
Okay, let me get this right? Are you claiming there are specialized parts of cortical region performing some specific complex functionality and not not being made of the "usual" cortical column (I know that cortical columns themselves vary to some degree, either in size or for physical/distance optimization issues, however I don't see why this would change the basic principles of their operation...) Or are you claiming this about the other non-cortical brain regions, which have different functionality?
but ignoring the fact that in actual intelligent brains declarative memory itself is managed by highly specialized non-cortical regions, and procedural memory is informed greatly by them as well.
I'm guessing here that you're talking about the Hippocampus (as far as non-procedural memory is concerned). Due to HM's case (
http://en.wikipedia.org/wiki/HM_(patient) ) it is known that hippocampal damage can cause one to be unable to form new "general"(?) memories (such as what you did today, the past week, etc), however procedural memories can still be formed. It appears that it's basically the edge of the cortex, and its circuit is not one of the most complex (
http://upload.wikimedia.org/wikipedia/commons/2/25/CajalHippocampus_(modified).png ). It may be that its functionality is not nearly as important in a generalized model (or more precisely, what I'm claiming is that the functionality performed by it may be needed biologically, however it might not be necessary in a high-level digital model which does not involve all the low-level details that the human brain must have to function).
Procedural memory can be handled by the cortex, however some of it is handled by non-cortex regions. I'll probably go more into this a bit later.
Behavior is part of that information, and in many cases the cortical processing is short-circuited by non-cortical regions.
Do you mean reflexes, such as those that can be performed as early as in the spinal cord/brainstem/cerebellum/... ?
Everything the cortex does somehow depends on more specialized regions.
Various sensory information may be filtered/prepared for it? Motor commands can be "unfolded" into more specific ones?
Self-directed entities need to learn and all of the extant, recognizably intelligent ones come with learning material which we call instinct.
Before the cortex had evolved (mamallians), you had the reptilian brain, which likely accounts of this "learning material". However, it is known that the cortex can take over most of this behaviour once learned. I do believe that when implementing an AI based on Hawkin's model, a way for providing default behaviour for training would be quite useful, however there are a few more problems with it: in his current implementation (HTM), he hasn't quite properly implemented any form of feedback (such as motor function in a real organism) and attention.
While one might be be able to "halfass" their way and avoid needing to implement every little detail of a real brain there are a few important things I believe are still missing from his implementation: a feedback mechanism (such as motor control), default behaviours for this feedback system ( what you called instincts) and attention (selecting specific paths while inhibiting others regardless of the default behaviour of projecting back fully). These mechanisms may not be needed for visual or auditory processing which is a common application he's been using HTM for, but they would be needed if you wanted to use his model to implement a general AI agent (embodied or virtual).
In the real brain, attention is handled by the Thalamus (relays things to/from the cortex and can select the active circuits in the cortex (attention)). The Thalamus controls sleep, and I believe this is probably done by just not passing in most sensory input to the cortex for further processing (same as the other attention-related behaviour).
As for the feedback (motor control), the neocortex projects it to the Brainstem/spinal cord/cerebellum/basal ganglia.
Cerebellum (low level motor control) has can project to the brainstem/spinal cord (and back and forth), as well as to the Thalamus (attention). Basal ganglia project to the Thalamus as well. I'm very curious of how he plans to implement feedback in his model, as he seems to skimp on this subject even in his book, even though it is important.
For a self-directed entity with real higher-order function, something more complex is needed and Hawkins' mistake is easy to make: that complexity is in the form of the same stuff as the memory model.
I don't think he ever claimed this. What I do believe I've seen him claim is that the more specialized parts are a lot more simpler, low-level and specialized to the organism. In a real world use scenario, you'd have to implement that sort of filtering/processing on your own to match the hardware (or virtual) model. Some lessons could be learned there from nature, but the most important lesson is the neocortical column.
He currently claims that HTM's aim is to model the Neocortex, Thalamus(although I've never seen this implemented in the HTM yet (attention getting)) and a bit of the Hippocampus (might not really be needed as it it could itself be viewed as the edge of the neocortex). He does not include the filtering (and default behaviour) provided by the sensors, nuclei, spinal cord, cerebellum, basal ganglia in his model as he probably views them as organism specific, and such behaviour would have to be programmed in through some other external mechanisms in a real implementation.
tl;dr: Hawkins' model isn't perfect, but it's likely a good one to build upon, and it should eventually be adjusted to handle some functionality which is not yet implemented/fully understood (feedback and attention). Hawkins never claimed his model was perfect or even good enough, although he's been focusing on the most important part (high-level sensory processing and cognitive functions), while avoiding the low-level sensory processing and motor parts.