Indeed! Behavioral studies taking place in “Primate Centers” have come under criticism and the most recent studies have been careful to show that the chimp troops studied are untainted by prior human contact as well as the experiments conducted designed for minimal chimp interaction with humans.
The current hypothesis on speech is that we have cerebral torque and they don’t. There is, however, some work that looked at their larynx development as well. The whole premise that the ‘Planet of the Apes’ franchise was built around is not too far fetched.
I guess I’m describing an exception to the rule. I agree that the generic-ness of cortex means a lot of things must originate conceptually from subcortical non-generic-ness.
Motives aren’t required for all behaviors. For example, TBT’s object layer could learn how to reduce ambiguity without RL. Volition must override that, but that sort of thing could be the background hum.
I’m convinced that the cortical motor output cells anchor locations to parts of objects.
Their apical dendrites reduce perceptual detection threshold, and they burst based on self-movement to correlate strongly with location. Those two things suggest they produce an anchoring signal.
For example, imagine digging around for a mug in a purse, to take a sip of coffee. Once you feel the handle, boom, you found it and know how to pick it up. You anchored locations to the mug.
If motor output isn’t an inherent part of the perceptual process, why would the cortical motor output cells anchor locations?
I think this exception might be a bridge to the mindset you advocate. Anchoring locations defines the spatial system, so it needs to anchor to the right information. The brain needs to produce its wide variety of spatial systems, so it could use subcortex for its non-generic-ness.
For example, anchoring to faces detected by subcortex could produce the fusiform face area. Getting things to actually work when implemented might require that. Even primary cortical regions have a lot to do with super complicated subcortical stuff. Like, check out S1 in this diagram:
This is an incredibly naive academic perspective. Work in any business involving the use of technology and you will see how wrong this is. Making money just cares about the organ grinder, not the organ. The financial crisis was all about a model that people knew was flawed but the music continued longer than it should have done, as just one example of many. Black Scholes is used by many in blind faith without any understanding and in a portfolio effect near on impossible to unpick it as a black box (as in one bank I worked at on a system to do just that 25 years ago with a massive portfolio).
In this instance, the cortex could not be completely passive, otherwise it means that what we think of as consciousness is just a layer (literal) of complexity like the curtain in Wizard of Oz. Maybe the logic of addiction is such an obvious conflict where the old/animal brain is still in charge and we just pretend it is not thinking our (perceived conscious) cortex is far too clever to get addicted to something we “know” and understand is bad for us.
Cocktail effect aside, if you have tinnitus you can filter out the frequencies and reduce them one by one, which is what I do to a degree as I can’t reduce the noise completely. They are high pitched white noise with certain frequencies. There is also the case of the guy who could identify many separate notes played on a piano all at one time.
What about bats or human echolocation ? All senses are the same in relation to the cortex, they are just an activation stream (blended/mixed), why think each is really any different ? Does the degree of perceived vectors really change the processing ?
Do you consciously ride a bike or is this a non cortex dominated activity (re the video of the cat walking with no cortex) ? Does this motion process just get a directional queue as to where to go or rather just a “delta signal from the cortex”. The motor aim of the mug is the animal desire for food (primary instruction guidance/activation origin) and the cortex just “alters” the motion rather than controlling it as such. Otherwise you end up with an activation issue of many parallel activations cross polluting if you think it’s all cortex sequence based. This is where I think some aspect of the TBT may be a bit wrong.
Let’s not confuse any of hemispherectomy, callosectomy, decortication and decerebration with a brain that has the ability to learn speech (only humans) and has learned speech (again, only humans).
My LOL for the day. Not disagreeing at all, just struck me funny. The sad fact is that we toiled in Machine Intelligence for years and barely had anything to show for it–then business came along and now we have working intelligent agents that can converse.
I’ll try to summarize why I don’t think cortex is passive. Everything else I said doesn’t matter much.
The motor output (L5tt) anchors locations.
A. The apical dendrites enhance perceptual detection, so a weaker stimulus will be noticed [1].
B. Upon active touch, motor copy signals sent to the apical dendrites cause firing strongly correlated with location in a coordinate-transformed spatial system [2, 3, also see 4].
Those are both consistent with L5tt cells sending signals which anchor locations being tracked by other neurons.
The same cells trigger anchoring and perceptual detection by apical firing modes. So anchoring is equivalent to perceptual detection.
So that aspect of attention happens by anchoring, not by thalamic filtering. Also, anchoring is a crucial part of perception, so I think it has to happen automatically, e.g. without reward.
So the cortex can cause things which volition can control (at least attentional shifts), so I don’t think the cortex is entirely passive.
I also argued for motor commands driven by purely perceptual processes. Remember, the cells I’ve been talking about are the cortical motor output. They’re absolutely involved in perception (for many reasons), so I expect that they produce perceptually-driven, non-motivated behaviors. Motivations can constrain / guide those behaviors and attention, of course.
I think that’s just filtering out sounds, not frequencies. Thalamic gain control is probably a thing, though. I guess my point was just that it feels like attending a visual object means you’re filtering out the rest, but it’s actually about anchoring egocentric locations to the object.
I think generic cortex is a thing. That doesn’t mean we experience vision the same way we experience touch. They’re different senses. We perceive things on the retina from a distance, so we need to deal with retinotopic things, like occlusion / line of sight. So it feels like it’s fundamentally retinotopic, but if we assume generic cortex, it’s not, because we don’t experience other senses topographically.
So attending objects by topographical filtering wouldn’t work well for generic cortex. So attending objects requires another mechanism, which I think is anchoring.
A link between anchoring and attention isn’t a new idea. I think the references thing brought up in some Numenta meetings is related to that, but I don’t really understand that so dunno.
To clarify, I wasn’t talking about motor control, just describing anchoring and its link to perceptual detection.
It probably doesn’t just modify behavior originating subcortically. vS1 has a direct pathway to a muscle [5]. That study did polysynaptic retrograde tracing, pretty cool.
Even if it just modifies ongoing behavior, the cortex would still have that parallel activations issue.
I think we need to be careful to keep things in perspective. On this point, no, no we don’t. As somebody who’s written a few chatbots, all that we have are very brittle detection models and a few neat tricks.
Not to say I don’t appreciate being able to ask some smart device what time it is, the weather, or to set a timer/alarm… those are all neat and useful. But I would shy away from saying that we have anything “intelligent” or with a real ability to “converse” beyond a tightly controlled and narrow dialogue/script. ELIZA is a lot of fun though. Eliza, Computer Therapist
I apologize. Perhaps it is naïve and aspirational. However, after having written firmware for a couple medical device projects, I see that there certainly is a bureaucratic system in place to gatekeep code which has the potential to directly impact peoples’ health; given that perspective and background, combined with the negative sentiment that many people have gathered about AI, facial recognition, the abuse of personal data for widespread abuse/manipulation via social media, it wouldn’t say yet that it’s beyond the realm of possibility that some system of review is imposed on systems that impact people outside of finance. As a matter of fact, because of the stringent requirements that medical devices are required to prove their code execution, I suspect that is one of the reasons we don’t see any real explosion of “AI” medical devices aside from some ‘smart’ watches which log your activity to the cloud for potential analysis… even still, these generally aren’t allow to be officially sold as ‘medical’ devices.
As for those stupid institutional high speed trading bots… I think you’re right. They’d need to cause another global financial catastrophe before government around the world might consider some restrictions on their activity. Even then, they’d be quietly rolled back a few years later, just as we saw with exotic derivatives trading activity.
I’m only arguing that the cortex can produce attentional shifts as part of sensory processing. We can do that intentionally too, so I don’t consider that a passive thing.
Discussions aren’t science, but they still have value.
I think everyone missed one of the base assertions: input of sensory data via the thalamus. This certainly can initiate activity and part of this activation can be recall, and loops through higher-dimensional search space. Continued inputs could certainly give rise to a continuous response. If you think about it, the cortex is actually passively responding but it could be a very rich response.
As to the volitional part - this is entirely done through the sub-cortex. A loop from the cortex to sub and back again is involved in command exchange. With the relatively small number of subcortical nodes and a large variety of levers to pull on the body, the subcortex can have some pretty powerful built-in patterns in some sort of genetic coding. I seem to recall reading that the large variety of neurotransmitters gives behavior shaping. I have read that we make decisions that we “become aware of” after the fact. “It” has to have a cortical presence to enter consciousness.
I have been chasing this for years and I keep reading paper after paper that is consistent with a very close partnership between all the brain elements. There is programming that takes place outside of cortical computations and this is where common sense and motivations come from.
This is the missing “ghost in the machine.”
With DSP processing it is relatively common to think of processing pipelines When considering what the cortical column is doing the bigger picture of what computations are being supported may shed some light. That has been helpful for me to understand HTM/TBT.
If the cortex can generate behaviors for non-volitional reasons, would you still consider the cortex passive? I’m just trying to understand what you’re saying.
Introspection is not science. Can you demonstrate empirically that this is so?
Discussions lead to hypotheses. How would you prove yours empirically?
Neuroanatomy is not the way to do it. What you’re looking for is a situation where an organism initiates a course of action that (a) does not rely on any current sensory input (b) does rely on a cortical capability such as constructing a timeline. Doesn’t sound too hard.
I think the discussion of active vs passive is misleading. The cortex is actively doing the things that it does, and passively not doing the things that it doesn’t do. The HTM theory says it is building a model of the world. There are complimentary theories explaining how attention (via apical dendrites) can be used to interrogate/manipulate the cortex’s model of the world.
The cortex is passive with respect to the process of action initiation. That is mostly done by the basal ganglia and brainstem.
An interesting note: The locus coeruleus is part of the brain stem, and it contains norepinephrine (aka the adrenaline rush hormone) releasing neurons. IIRC the release of norepinephrine is critical for starting an action. The following review article (which i have not yet read beyond the abstract) says that the frontal cortex projects directly to the locus coeruleus and controls it in-sync with the animals behavior.
I agree introspection isn’t science. I just think hypotheses matter a lot for figuring out how intelligence works, considering the history of AI winters and what I know about neuroscience. That’s just an opinion.
I can’t because I’m not a neuroscientist, but if you’re asking whether it’s provable, “L5tt sends signals to location-representing neurons which anchor locations” is very specific. The second part, “anchoring locations is equivalent to perceptual detection mechanism-wise” is also very specific, because it’s really about whatever the exact mechanism is. I don’t know what it is, but something apical, if it exists. The rest is basically just semantics and why I think cortex isn’t passive.
If you really need exact examples of ways to test the hypothesis
Do L5tt cells have a synaptic pathway by which they could anchor cortical grid cells?
Do L5tt cells correlate with locations upon perceptual detection in other cortical regions and species? This doesn’t require figuring out the spatial system because cortical grid cells are a thing. L5tt cells shouldn’t be grid cells, I think, because they’re producing a signal which strongly correlates with location by combining sensory / motor information. That means they should include extraneous information, and better predict the resulting activity of grid cells better than vice-versa.
Do cortical grid cells no longer anchor their locations upon perceptual detection if the apical dendrites of L5tt cells are silenced?
What’s the exact mechanism, and does it work when implemented in code? Does the exact mechanism exist in generic cortex?
I never said the organism initiates a course of action which doesn’t rely on any current sensory input.
Maybe the cortex is passive in the sense that it reacts to sensory input (and external inputs from subcortex, whereas subcortex wants stuff and has emotion things like amygdala)?
I was thinking about it in the sense that, we can intentionally do xyz, so the cortex isn’t passive if it can do any of that, because it’s sending something like a command.
I guess if by passive you mean lacking its own volition, intention, desires then it would make more sense to everybody.
It might be quite active otherwise by doing … its stuff, which probably can be summarized as … knowing
Well, I’m not sure that’s what you mean, this is actually a question.
