the thalamus has a distinctive central role in what may be the highest function of consciousness: making decisions.
Decision making is arguably the highest conscious function since it requires marshalling all of the information of the senses and cortex to contribute to the decision. Discrimination and deciding are the constant tasks of consciousness, happening dozens of times per second.
Edit: I think I may have been somewhat hasty and neglected subjective awareness. The discussion in the first part of the post really centers around subjective awareness, as mentioned by Ned Block in the clip I link as well as being the positive clinical result of Chudy et al. (2023, the study that had unresponsive patients return to full awareness after thalamus deep brain stimulation). This is very directly what that opening line is referring to as this research is very recent.
The post really addresses both of these: subjective awareness/experience and decision making. They are also intimately related; as I say in my follow up the qualia of subjective experience are inputs to the decision making function.
And let me somewhat refine “decision:” we are talking about a consensus mechanism in the brain, so the “decision” of the unitary individual consciousness or mind happens in the thalamus, similar to how the decision on a bill happens in the Senate Chamber through a method of combining information from senators. “Decisions” are also made by individual senators on how to vote, possibly involving other still further removed “decisions” in the causal process from lobbying groups or individual voters. But we still view the “decision” of The Senate to happen in the Senate Chamber during a vote, similarly to how the “decision” of the mind through the consensus mechanisms of the thalamus and TRN happens in the thalamus and TRN, even if cortical areas make their own disparate “decisions” in smokey backrooms of the cortex.
One area of “decision” that the thalamus is involved in is attentional filtering of external sensory information. I mention that here:
I would speculate that an evolutionary story is that the thalamus moved from a role of filtering incoming sensory information for attentional purposes to filtering internal thoughts for similar attentional and reinforcement purposes. The thalamus extended from the task of deciding to which sensory patterns the mind attends to more general decision making. This evolutionary story is a strong argument to conceive of decision making as happening in the thalamus despite being influenced by the cortex and the decision-making process being inherently looped; the thalamus or thalamus-like structures have been making decisions since before there was a neocortex.
This sort of happens before conscious thought in adult human systems, although embryonically and evolutionarily it happens before the neocortex and consciousness exist.
Conscious decision making is a subset of overall decision making, perhaps, but it is the highest function of consciousness. Elements of consciousness like sensory and emotive qualia are there to push information into this particular function of consciousness: decision making.
I agree with most of that. Consciousness is how we make our important decisions.
I don’t think there are ever dozens per second of what we would call decisions. More like one or two or at most ten, even if we scratch the meaning of decision. That’s about how long it takes for the cortical basal ganglia loop to reverberate enough to really activate that representation.
10 is the absolute maximum you’d get on an alpha cycle, but I don’t think it’s plausible that just went alpha cycle is enough for what would really call a decision.
And if we are talking about consciousness, I am going to say I have tried to introspect about this a lot, and I have never caught what would seem like more than two conscious decisions in one second. More like a full second for most decisions, even in action games, and often many seconds per decision when I’m thinking about them.
More like a full second for most decisions, even in action games, and often many seconds per decision when I’m thinking about them.
I mean, I’ve done those FPS reaction time trainer things and I can feel the limit at about 200 ms, which is basically a notice decision and fire decision. I can maybe get a little lower but to do so I feel like I am potentiating actions and then canceling them until the dot pops up and I allow the action to go through. This isn’t the one I’ve used in the past (there were dots that popped on a field and you needed to mouse over to them and click on them).
It has a nice graph that shows a peak for their users at around 200ms.
But that sort of thing “the dot has popped up over here” is a decision of a kind at least and involves the choice of that option over “the dot has not popped up over here.” Whether it is a “conscious decision” is a different matter; we are certainly aware of all the inputs to the decision, but the idea that it is itself a decision is not something we think about most of the time, unless we’re having an esoteric conversation like this.
How much of riding a bike is a decision? You could certainly lose your balance on purpose at basically any moment; you expend some mental effort in keeping yourself balanced. Are those “decisions?” At this point it is semantics.
What is clear is that the thalamus provides the unitary consensus of the mind so that you don’t do things like believe an object is two things at once (unless you’re on some heavy drugs).
Yes, I agree. Conscious decisions that firmly fit the definition take a lot longer.
Oh hey! if you do want to know my theory about decisions, I did write a whole article about it for a “real prestigious scientific” journal: Neural mechanisms of human decision-making
You sound like one of the very few humans who might be interested.
Warning: when I wrote that, I was worried that writing it too clearly or persuasively might give AI developers too many good ideas and shorten timelines. I also had a boss/collaborator with different ideas about how to frame things. So I compromised on partly clear writing about my own carefully thought-out theories, and partly scientifical jargon speak that would get it published in a good journal but interest or elighten almost no one.
From the conclusion:
Decision making is arguably the highest conscious function since it requires marshalling all of the information of the senses and cortex to contribute to the decision. Discrimination and deciding are the constant tasks of consciousness, happening dozens of times per second.
Edit: I think I may have been somewhat hasty and neglected subjective awareness. The discussion in the first part of the post really centers around subjective awareness, as mentioned by Ned Block in the clip I link as well as being the positive clinical result of Chudy et al. (2023, the study that had unresponsive patients return to full awareness after thalamus deep brain stimulation). This is very directly what that opening line is referring to as this research is very recent.
The post really addresses both of these: subjective awareness/experience and decision making. They are also intimately related; as I say in my follow up the qualia of subjective experience are inputs to the decision making function.
And let me somewhat refine “decision:” we are talking about a consensus mechanism in the brain, so the “decision” of the unitary individual consciousness or mind happens in the thalamus, similar to how the decision on a bill happens in the Senate Chamber through a method of combining information from senators. “Decisions” are also made by individual senators on how to vote, possibly involving other still further removed “decisions” in the causal process from lobbying groups or individual voters. But we still view the “decision” of The Senate to happen in the Senate Chamber during a vote, similarly to how the “decision” of the mind through the consensus mechanisms of the thalamus and TRN happens in the thalamus and TRN, even if cortical areas make their own disparate “decisions” in smokey backrooms of the cortex.
Unconscious decision making is a thing.
One area of “decision” that the thalamus is involved in is attentional filtering of external sensory information. I mention that here:
This sort of happens before conscious thought in adult human systems, although embryonically and evolutionarily it happens before the neocortex and consciousness exist.
Conscious decision making is a subset of overall decision making, perhaps, but it is the highest function of consciousness. Elements of consciousness like sensory and emotive qualia are there to push information into this particular function of consciousness: decision making.
If what the thalamus is doing is decision making (conscious or unconscious), it could be expressed as such.
I agree with most of that. Consciousness is how we make our important decisions.
I don’t think there are ever dozens per second of what we would call decisions. More like one or two or at most ten, even if we scratch the meaning of decision. That’s about how long it takes for the cortical basal ganglia loop to reverberate enough to really activate that representation.
10 is the absolute maximum you’d get on an alpha cycle, but I don’t think it’s plausible that just went alpha cycle is enough for what would really call a decision.
And if we are talking about consciousness, I am going to say I have tried to introspect about this a lot, and I have never caught what would seem like more than two conscious decisions in one second. More like a full second for most decisions, even in action games, and often many seconds per decision when I’m thinking about them.
I mean, I’ve done those FPS reaction time trainer things and I can feel the limit at about 200 ms, which is basically a notice decision and fire decision. I can maybe get a little lower but to do so I feel like I am potentiating actions and then canceling them until the dot pops up and I allow the action to go through. This isn’t the one I’ve used in the past (there were dots that popped on a field and you needed to mouse over to them and click on them).
https://humanbenchmark.com/tests/reactiontime
It has a nice graph that shows a peak for their users at around 200ms.
But that sort of thing “the dot has popped up over here” is a decision of a kind at least and involves the choice of that option over “the dot has not popped up over here.” Whether it is a “conscious decision” is a different matter; we are certainly aware of all the inputs to the decision, but the idea that it is itself a decision is not something we think about most of the time, unless we’re having an esoteric conversation like this.
How much of riding a bike is a decision? You could certainly lose your balance on purpose at basically any moment; you expend some mental effort in keeping yourself balanced. Are those “decisions?” At this point it is semantics.
What is clear is that the thalamus provides the unitary consensus of the mind so that you don’t do things like believe an object is two things at once (unless you’re on some heavy drugs).
Yes, I agree. Conscious decisions that firmly fit the definition take a lot longer.
Oh hey! if you do want to know my theory about decisions, I did write a whole article about it for a “real prestigious scientific” journal: Neural mechanisms of human decision-making
You sound like one of the very few humans who might be interested.
Warning: when I wrote that, I was worried that writing it too clearly or persuasively might give AI developers too many good ideas and shorten timelines. I also had a boss/collaborator with different ideas about how to frame things. So I compromised on partly clear writing about my own carefully thought-out theories, and partly scientifical jargon speak that would get it published in a good journal but interest or elighten almost no one.
Make of that what you will.