https://www.msn.com/en-us/health/other/thalamic-nuclei-observed-driving-conscious-perception/ar-AA1Cx8yH?ocid=socialshare

From the article:

"Beijing Normal University-led researchers have identified specific high-order thalamic nuclei that drive human conscious perception by activating the prefrontal cortex. Their findings enhance understanding of how the brain forms conscious experience, offering new empirical support for theories that assign a central role to thalamic structures rather than cortical areas alone."

This finding appears to abut nicely to my thoughts on the central role of the thalamus in the emergence of our sense of self.

Edited August 1Aug 1 by DrmDoc
spelling

1 hour ago, DrmDoc said:

From the article:

That’s a great write up, and agree absolutely overlaps with the thoughts you’ve been exploring here more recently than in years past.

I’m going to take as given that thalamus seems highly likely to be the initiation point for consciousness. My thoughts then lead to…

How far down on the evolutionary tree of life can we go before finding organisms that no longer have basic thalamic like structures and before finding something they can no longer be considered in some remedial basic way to be moderately mildly conscious themselves?

1 hour ago, DrmDoc said:

This finding appears to abut nicely to my thoughts on the central role of the thalamus in the emergence of our sense of self.

These findings show thalamus has a role in conscious perception - which is not necessarily the same thing as a sense of self. And the article only suggests thalamic loops are another part of the consciousness picture, along with cortical areas and others, not that it is central.

16 hours ago, TheVat said:

These findings show thalamus has a role in conscious perception - which is not necessarily the same thing as a sense of self. And the article only suggests thalamic loops are another part of the consciousness picture, along with cortical areas and others, not that it is central.

Although I believe your perspective may have some merit, I think the insight the article speaks for itself by "offering new empirical support for theories that assign a central role to thalamic structures rather than cortical areas alone."

16 hours ago, iNow said:

That’s a great write up, and agree absolutely overlaps with the thoughts you’ve been exploring here more recently than in years past.

I’m going to take as given that thalamus seems highly likely to be the initiation point for consciousness. My thoughts then lead to…

How far down on the evolutionary tree of life can we go before finding organisms that no longer have basic thalamic like structures and before finding something they can no longer be considered in some remedial basic way to be moderately mildly conscious themselves?

I think that's a great question and, as I now consider, all organisms along the evolutionary chain were likely biologically driven by variance of homeostasis and any that acquired a response system sufficient to maintain homeostasis--neural or otherwise--may have been capable of evolving behaviors suggestive of intelligent awareness--awareness that distinguishes thoughtful behaviors from those we may perceive as instinctive.

Edited August 2Aug 2 by DrmDoc

56 minutes ago, DrmDoc said:

new empirical support for theories that assign a central role to thalamic structures

While I’m largely convinced of the conclusion, I wouldn’t lean too heavily on this particular point.

Because the test group involved people with specific brain implants it’s IMO unreasonable to expect a huge sample, but the N sample size noted is pretty small overall and we should thus limit our desire to generalize.

2 hours ago, DrmDoc said:

Although I believe your perspective may have some merit, I think the insight the article speaks for itself by "offering new empirical support for theories that assign a central role to thalamic structures rather than cortical areas alone."

@TheVat is right. I see that the usage of the word in this case can be easily misleading if you misinterpret the context. I'm pretty sure the word "central" simply means critical or key here. This shouldn't be confused with it being the "centre of consciousness". The article doesn't explicitly state that the thalamus is the centre.

Edited August 2Aug 2 by DavidWahl

I read it as core role. Important role. Key role. Critical role. Central role isn’t vastly different unless we’re actively looking hard for criticisms to levy… especially since the thread title uses the term drive.

“The mother played a central role in driving the family in their minivan.”

“Nuh uh! She sits up front, on the left side actually, not in the center!”

🙄

4 hours ago, iNow said:

I read it as core role. Important role. Key role. Critical role. Central role isn’t vastly different unless we’re actively looking hard for criticisms to levy… especially since the thread title uses the term drive.

“The mother played a central role in driving the family in their minivan.”

“Nuh uh! She sits up front, on the left side actually, not in the center!”

🙄

From what I’ve read so far, it seems like you guys are quite convinced that the thalamus is the primary source of consciousness, not just a contributing part. That’s what I meant by the phrase "centre of consciousness" (figuratively). It also seems like the terms "central role" and "centre of consciousness" are being used interchangeably here, even though they convey very different ideas.

15 hours ago, iNow said:

While I’m largely convinced of the conclusion, I wouldn’t lean too heavily on this particular point.

Because the test group involved people with specific brain implants it’s IMO unreasonable to expect a huge sample, but the N sample size noted is pretty small overall and we should thus limit our desire to generalize.

Much like my opinion on political polls, I agree that small samplings are not always representative of larger groups. I believe we can both agree that flaws can be found in most if not all studies. However, as you may have preceived through our previous discussions, my thoughts about the thalamus doesn't hinge on single studies but rather the cumulative empirical evidences these studies appear to provide overall. As the author of this article assesses, these Beijing's findings offers support for the role of the thalamus--much like a single vote casted in some grand election.

14 hours ago, DavidWahl said:

@TheVat is right. I see that the usage of the word in this case can be easily misleading if you misinterpret the context. I'm pretty sure the word "central" simply means critical or key here. This shouldn't be confused with it being the "centre of consciousness". The article doesn't explicitly state that the thalamus is the centre.

I agree and neither have I in my comments here. If you'll recall my initial comments, I said I beiieve the findings this article reveals support my thoughts on the "central role of the thalamus in the emergence of our sense of self."

6 hours ago, DavidWahl said:

From what I’ve read so far, it seems like you guys are quite convinced that the thalamus is the primary source of consciousness, not just a contributing part. That’s what I meant by the phrase "centre of consciousness" (figuratively). It also seems like the terms "central role" and "centre of consciousness" are being used interchangeably here, even though they convey very different ideas.

The article provides support for other research that details the dependence of cortical function on thalamic function. That research empirically details the neural path all sensory afference must traverse to reach our cerebrum. Every sensory neural pathway--other than olfactory--that fills our brain with data about our environment and self, converge at the thalamus first and it is the thalamus that relays or disseminates that data throughout the cerebrum.

We derive our sense of self from the data our brain receives about our environment and self--and if it's the thalamus that disseminates that data, then why is it so difficult to believe that our sense of self emerges from or through the thalamus?

Edited August 3Aug 3 by DrmDoc
clarification

8 hours ago, DavidWahl said:

seems like you guys are quite convinced that the thalamus is the primary source of consciousness

I’m convinced it plays a key, critical, core, important, one might even say central role.

1 hour ago, DrmDoc said:

my thoughts about the thalamus doesn't hinge on single studies but rather the cumulative empirical evidences these studies appear to provide overall.

Same, and decades ago one of my neuroscience professors always said something which stuck with me: All roads lead through thalamus.

3 hours ago, DrmDoc said:

The article provides support for other research that details the dependence of cortical function on thalamic function. That research empirically details the neural path all sensory afference must traverse to reach our cerebrum. Every sensory neural pathway--other than olfactory--that fills our brain with data about our environment and self, converge at the thalamus first and it is the thalamus that relays or disseminates that data throughout the cerebrum.

We derive our sense of self from the data our brain receives about our environment and self--and if it's the thalamus that disseminates that data, then why is it so difficult to believe that our sense of self emerges from or through the thalamus?

That's very plausible, though the only thing that keeps me a bit skeptical is the olfactory part. Based on my limited understanding, one definite takeaway is that the thalamus seems deeply involved in maintaining the coherence of conscious experience. It's likely, what they would say, the conductor behind the illusion of unity and continuity of subjective experience.

Edited August 3Aug 3 by DavidWahl

18 minutes ago, DavidWahl said:

the only thing that keeps me a bit skeptical is the olfactory part. Based on my limited understanding, one definite takeaway is that the thalamus seems deeply involved in maintaining the coherence of conscious experience

I believe the point is that, while thalamus is critical in organizing all incoming stimulus, olfaction involves even more archaic neural structures and doesn’t flow straight through thalamus from the start like inputs from essentially ever other source do.

Edited August 3Aug 3 by iNow

On 8/3/2025 at 4:49 PM, iNow said:

I believe the point is that, while thalamus is critical in organizing all incoming stimulus, olfaction involves even more archaic neural structures and doesn’t flow straight through thalamus from the start like inputs from essentially ever other source do.

I'm surprised that olfaction and taste are routed so differently. A little research tells me that taste sensations are routed through the thalamus on their way to the gustatory complex. And yet taste and smell seem so closely coupled in our overall perception of eg bacon that they almost act as one. Very curious.

2 hours ago, sethoflagos said:

I'm surprised that olfaction and taste are routed so differently. A little research tells me that taste sensations are routed through the thalamus on their way to the gustatory complex. And yet taste and smell seem so closely coupled in our overall perception of eg bacon that they almost act as one. Very curious.

Although gustatory and olfaction operate to provide the brain with an encompassing sense of flavor, from my understanding of brain evolution, they are routed differently because taste perception had the most immediate impact on ancestral species' survival, which required immediate survival responses. Those immediate responses initiate through the thalamus. Olfaction was useful to ancestral species for the immediate but indirect detection or predation of food sources, while gustatory or taste required species to have direct and perilous physical contact with those food sources. Smell made ancestral animals aware of potential food sources without physical risk and taste was likely adapted as these animals learned to mediate what smelled good by what was safe to consume.

6 minutes ago, DrmDoc said:

Although gustatory and olfaction operate to provide the brain with an encompassing sense of flavor, from my understanding of brain evolution, they are routed differently because taste perception had the most immediate impact on ancestral species' survival, which required immediate survival responses. Those immediate responses initiate through the thalamus. Olfaction was useful to ancestral species for the immediate but indirect detection or predation of food sources, while gustatory or taste required species to have direct and perilous physical contact with those food sources. Smell made ancestral animals aware of potential food sources without physical risk and taste was likely adapted as these animals learned to mediate what smelled good by what was safe to consume.

So taste is the more basal sense? Hard to imagine how 'smell' operates in a marine environment where I presume both originated.

Incidentally, I would have thought consciousness was an example par excellence of an emergent phenomenon, and therefore would not really have a 'centre' as such; it being a more distributed, non-localised product of the sum of its many parts. Though the crucial importance of the thalamus within the network seems to be... for want of a better word... emerging.

12 minutes ago, sethoflagos said:

So taste is the more basal sense? Hard to imagine how 'smell' operates in a marine environment where I presume both originated.

It would likely have operated the same as it does now in a land based environments. Olfaction essentially involves the detection of scent molecules that can carry well through both water and air environments.

18 minutes ago, sethoflagos said:

Incidentally, I would have thought consciousness was an example par excellence of an emergent phenomenon, and therefore would not really have a 'centre' as such; it being a more distributed, non-localised product of the sum of its many parts. Though the crucial importance of the thalamus within the network seems to be... for want of a better word... emerging.

If we're settled on "emerging", isn't it reasonable to conclude that our sense of self emerges through our experiences and if we're discussing where detection of those experiences initially converge in the brain before manifesting as consciousness, then the thalamus is likely that solitary brain structure from which our sense of self emerges.

Edited August 5Aug 5 by DrmDoc
spelling

4 hours ago, sethoflagos said:

I'm surprised that olfaction and taste are routed so differently

It’s a far more reptilian part of our brain. I was surprised too when I first learned it, but it makes intuitive sense.

1 hour ago, sethoflagos said:

Hard to imagine how 'smell' operates in a marine environment where I presume both originated.

My understanding is sharks can smell a single drop of blood almost half kilometer away.

1 hour ago, DrmDoc said:

then the thalamus is likely that solitary brain structure from which our sense of self emerges.

I was with you until you said solitary. Is that maybe the case? Sure, but sense of self strikes me as one of those things where the sum of the parts is greater than the whole.

On 8/3/2025 at 7:02 AM, iNow said:

Same, and decades ago one of my neuroscience professors always said something which stuck with me: All roads lead through thalamus.

Same here, but my professor also made the same remark about the corpus callosum. The good doctor should see that all roads lead through many a nexus, but those nexuses are not singular loci for a global emergent process. All roads in Midwest America might lead through Chicago but that doesn't mean the Midwest ceases to be if all the roads there are bombed. No doubt some commerce would reroute through Twin Cities and St Louis and KC and Omaha, and various modules of Midwestern life would manage to limp on.

Neurological roads connect many modules that participate in consciousness and selfhood, somewhat in line with Marvin Minsky's Society of Mind (see also Daniel Dennett) but they are not themselves some defining receptacle of consciousness. The switchboard is not the conference call. What is necessary for something is not always the thing itself.

Believe the final comment from me on the post immediately preceding yours touched on similar theme

Hi DrmDoc,

I think one should read this very precisely.

On 8/2/2025 at 1:14 AM, DrmDoc said:

"Beijing Normal University-led researchers have identified specific high-order thalamic nuclei that drive human conscious perception by activating the prefrontal cortex. Their findings enhance understanding of how the brain forms conscious experience, offering new empirical support for theories that assign a central role to thalamic structures rather than cortical areas alone."

I made the the important phrases bold.

activating the prefrontal cortex: One can read this as: the thalamus selects where consciousness is needed. For consciousness, the prefrontal cortex must be activated

rather than cortical areas alone: I read this as, the prefrontal cortex has no direct connection with the senses. The thalamus makes some kind of 'pre-selection' when consciousness is needed,

Both are supported by the observation that when learning something new, consciousness is heavily involved. But with enough training, one sometimes can react correctly before consciousness is even involved. (Consciousness is relatively slow).

Then look at the symptoms when somebody suffers a stroke in the thalamus:

• absent or abnormal sensation on one side of the face, arm, and leg

• sensory changes involving:

• touch

• pain

• temperature

• pressure

• vision

• hearing

• taste

• mild or moderate weakness on one side of the body

My interpretation would be that that because of the stroke the pathways to other parts of the brain are disturbed.

And from the article's final paragraphs:

These findings add direct human evidence to support theories proposing thalamic nuclei as a gateway for conscious perception. Results challenge models that assign primary responsibility for awareness to the cortex alone.

Bold by me again.

From that it follows that I do not agree that iNow's proposal would work:

On 8/2/2025 at 2:49 AM, iNow said:

How far down on the evolutionary tree of life can we go before finding organisms that no longer have basic thalamic like structures and before finding something they can no longer be considered in some remedial basic way to be moderately mildly conscious themselves?

Maybe all 'higher organisms' have a thalamus. But they are missing the cortex that would make their actions conscious actions. AFAIK all vertebrates have a thalamus.

On 8/2/2025 at 1:14 AM, DrmDoc said:

This finding appears to abut nicely to my thoughts on the central role of the thalamus in the emergence of our sense of self.

Here I completely agree with @TheVat: sense of self and consciousness are not the same thing.

12 hours ago, sethoflagos said:

Incidentally, I would have thought consciousness was an example par excellence of an emergent phenomenon, and therefore would not really have a 'centre' as such; it being a more distributed, non-localised product of the sum of its many parts.

Same for me.

11 hours ago, DrmDoc said:

If we're settled on "emerging", isn't it reasonable to conclude that our sense of self emerges through our experiences and if we're discussing where detection of those experiences initially converge in the brain before manifesting as consciousness, then the thalamus is likely that solitary brain structure from which our sense of self emerges.

No. I hope you see why in my above comments.

1 hour ago, Eise said:

I do not agree that iNow's proposal would work

As always, your points are clear, consistent, and coherent and it's hard for me to challenge them given their strength. The one item which stands out to me right now, however (and it's possible I'm misinterpreting), is that you seem to be suggesting cortex is required for conscious experience (as do the authors you cited). I am not ready to accept that conclusion myself.

40 minutes ago, iNow said:

you seem to be suggesting cortex is required for conscious experience

Yes, but same as the authors of the article: not the cortex alone.

There's quite a bit here that's clearly desevering of a focused response, but it's clear that my perspective requires some clarification centered around my meaning of emergence and sense of self. Correct me if I'm mistaken, but I believe we all agree that our sense of self--our sense of whom and what we are relative to our mental, social, and physical environment--is solely dependent on the the information our brain receives and experiences. If true, that empirically renders our sense of self as secondary to that information, which means our sense of self--relative to brain function--is a response to information about self and that response cannot emerge within or through brain function without that information.

For those of us who are fimiliar with the anatomy of our central nervous system (CNS), we know that information about ourselves and our environment is channelled as sensory afference into the hierarchy of our CNS through that heirarchy's afferent neural connections to our body's sensory array. Given this perspective, one might say that it's our sensory array that gives rise to our sense of self, but that wouldn't be, IMO, precisely true. Our sensory array merely provides our brain with information about the separate and diverse affects of life experience, but where those affects initially converge and combine in the brain as an all encompassing sensory perception of self and our environment is indeed the thalamus.

Although the corpus callosum serves a critical function as @TheVat noted, that function merely combines the processing power of the two hemispheres after they have received data from the thalamus and its relays through other subcortical structures. Unlike the bombing of all roads to the midwest through Chicago in @TheVat analogy, destruction of the thalamus is fatal to brain function but not the other way around. Abraham Lincoln who, for example, sustain no thalamic damage but did sustain critical damage to his cortex, would have survived his assailant's attack if physicians were as knowledgeable then about brain swelling and wound treatment as they are now. There's a reason why the thalamus is shielded by cortical structure and why the cortex mirrors the thalamus' hemispheric configuration--but that's a discussion for another time.

Consciousness, by my definition, is merely that measure of awareness suggested by an organism's responses to stimuli. Relative to brain function, consciousness is an efferent product of brain function that does not occur or emerge without the brain's afferent neural connections to the thalamus, which is what I believe the article findings clearly suggest. Relative to emergence, in my view, consciousness and our sense of self are merely the lights (efference) switched on in brain function by thalamic function (afference).

20 hours ago, Eise said:

Yes, but same as the authors of the article: not the cortex alone.

Thanks for confirming. According to this view, even an octopus cannot be conscious so I reject it from the start.

On 8/5/2025 at 9:31 PM, TheVat said:

my professor also made the same remark about the corpus callosum

They were mistaken IMO. People born without it may have various deficiencies of various severities, but they still can function, lead healthy lives, and are very much conscious when they do.

2 hours ago, iNow said:

Thanks for confirming. According to this view, even an octopus cannot be conscious so I reject it from the start.

Good counter example. Then it would be interesting to give an octopus a some tasks in an MRI. But I foresee some practical problem with such a setup... 😉

The background of my arguments, is that our consciousness is an emergent property of the nervous system as a whole. That could be true for an octopus as well. At least they also seem capable of learning. So from my, admittedly 'Dennettian view', would be if his 'multiple draft' model of consciousness could also work for the different organised nervous system of an octopus.