22 ms·

Temporal circuit of brain activity supports human consciousness

416 points by hhs 7y ago

jkhdigital 7y ago
Man, I love seeing more research like this. My personal experience, as someone who has dealt with a variety of issues in psychiatrists' offices and rehabilitation rooms, is that a clear scientific understanding of what is actually going on under my skull provides a much firmer basis for any therapeutic approach. I'm really hoping that in my lifetime we will see connections made between the physiological elements of consciousness and the modern psychiatric plagues of depression, anxiety, and addiction that finally produce the targeted, universally effective therapies that are desperately needed.
- kohtatsu 7y ago
  I was recently talking to a registered psych nurse, and we got talking about Cognitive Behavioural Therapy. I believe I've been self administering a form of it for a couple years, and I summarized my understand of CBT as "moving more thinking from the amygdala to the prefrontal cortex", and she confirmed that with "in laymen's terms; yes". It's not like the fields are completely isolated, I guess is what I'm getting at with that anecdote. It's hard to go from neuroscience to psychology, but that's always being looked at. I reckon most big advancements will start coming when we start understanding the connectome more, but it's not like all advancements will come from there, and it's not like people aren't working right now to bridge neuroscience and psychology. Also I want to hang out with the laymen she does.
  - rhcom2 7y ago
    Do you mind sharing your approach to how you make that shift from "amygdala to the prefrontal cortex"? Is it similar to practicing mindfulness with a focus on the now?
    - mettamage 7y ago
      No, prefrontal cortex is about planning, reasoning and inhibiting emotions (we do it all the time without realizing) among a lot of other things. Amygdala is based on reacting to fear, among other emotions. CBT gives you a toolset to ask yourself questions to understand (a) which perspective you're currently looking things from and (b) which other perspectives you could use. The 10 cognitive distortions and recognizing them is a good start. Cognitive distortions happen mostly through emotional processes (e.g. the amygdala but the whole limbic system really). Mindfulness meditation is an emotional-based approach as it mostly relates (for laymen like me) to scanning the body. Scanning the body gives marked improvements to the insular cortex. It also gives marked improvements to the PFC (the inhibition part, not the planning part). This is all written way too short and my knowledge is a bit stale on it. I used to be really into this a couple of years ago. It was during the time when I studied psychology (I even published a neuroscientific literature review :D).
      - Enginerrrd 7y ago
        I love the spirit of your response, but I feel the need to disagree a bit and elaborate about your statement: >Mindfulness meditation is an emotional-based approach as it mostly relates (for laymen like me) to scanning the body The REAL essence and power of mindfulness is becoming aware of the contents of your attention. For some reason, focusing the attention inwards on bodily somatosensory experiences tends to encourage that, but the two are not the same. Body-scanning is more a technique to help encourage the development of mindfulness rather than the end goal in itself. The reason this distinction is so important and powerful is that the brain regions which are feeding the contents of your attention are the ones that get reinforced. When you combine mindfulness with practice in redirecting your attention, it becomes an insanely powerful tool to fundamentally reshape your reality by restructuring your brain.
        uoaei 7y ago
        Yes exactly. The "mindfulness" designation is a recursive one, where first you are mindful, then you are mindful of that which is mindful, and all the way down.
  - curo 7y ago
    I'm not qualified to contest this, but I do remember a side blurb from "Principles of Neuroscience" (Kandel, Schwartz, Jessell) that said overactive mPFCs are attributed with autism and below is some more research on it. I don't think you're saying this overtly but I have seen people from the Thinking Fast & Slow crowd glorify their PFCs as arbiters of cognitive bias while forgetting that healthy social, emotional processing required integrated functioning between all neural correlates involved, including the amygdala. I would venture to guess CBT is effective because it stops overactive PFCs which is the opposite of what the nurse's guess is. But as a laymen here, I can't say one way or the other. I remember a decade or two ago, the ACC+vmPFC combo was getting a lot of praise as this balancing force between the dlPFC and the amygdala saying strong ACC+vmPFC could be the clue to healthy brains. I think the answer will always be, "hey all these parts are important. Just meditate, exercise, and eat right. And don't believe your thoughts too much (CBT)" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5192959/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5192959/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4688328/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4688328/
    - deleted 7y ago
      [deleted]
    - fsloth 7y ago
      As a depression patient, that's more or less healed, here's my take: - In depression you can get up lost in these cognitive negative loops - One of the feedback loops is between what you feel and what you think - a bad feeling induces you to think some bad thoughts, and as those thoughts are combined with the bad feeling, they are validated as true. Now the thought is associated with a bad feeling, and one will give rise to the other , just like tinkle of the bell induced pavlov's dog to drool. But in this case the drooling of the dog can also make the bell tinkle, causing more drooling... - the amygdala response is about the bad feelings, and how the bad feelings can induce more physiological discomfort due to amygdala kicking in and doing "what it's supposed to" - now your bad feelings are superchardged as well - so, I would say it's not only about cortex or amygdala, but in depression the negative thought patterns and the physiological response can get linked into this destructive loop of continuous feedback. Hence, it does not matter that you can rationally say to yourself the bad thoughts you had are not that serious because they just launched a full scale amygdala based storm of bad feeling and anxiety - my ssri:s kind of felt like they cut out this bad loop. I felt like my cognitive self was insulated from the physiological response, giving me space to unlearn both cognitive and emotional bad habits one at a time without the disruptive loop taking control
  - arminiusreturns 7y ago
    Funnily enough, many combat vet friends of mine have had the most returns from two things which both seem to affect the brain in the same manner: cannabis and CBET. On the former, I can't recall who at the moment but there is significant research that has shown the primary cause of cannabis being so well received by those with ptsd is that is reduces amygdala activity and increases pfc activity.
- trub 7y ago
  psychedelic plant medicine is highly effective
ta1234567890 7y ago
Sounds like the temporal circuit is acting like a clock, as in a computer chip's clock. Pretty cool. > We demonstrate that the transitions between default mode and dorsal attention networks are embedded in this temporal circuit, in which a balanced reciprocal accessibility of brain states is characteristic of consciousness. Conversely, isolation of the default mode and dorsal attention networks from the temporal circuit is associated with unresponsiveness of diverse etiologies. These findings advance the foundational understanding of the functional role of anticorrelated systems in consciousness.
naasking 7y ago
The anti-correlated behaviour of these two networks, and even their default mode vs. attention functions, reminds of the attention schema theory of consciousness [1]. Specifically, the attention schema theory posits that some constant back and forth signal switching between internal and external models of the world results in the illusion of subjective awareness, in an analogous manner to how task switching provides the illusion of parallelism on single-core CPUs. [1] https://www.frontiersin.org/articles/10.3389/fpsyg.2015.00500/full https://www.frontiersin.org/articles/10.3389/fpsyg.2015.0050...
- hirundo 7y ago
  So psuedo basic for the consciousness algorithm: 10 look at world 20 look at my reaction to world 30 goto 10 Which generates consciousness like frames per second generates motion. Or like the colored lines over this black and white photo generate a color image: https://twitter.com/SteveStuWill/status/1248000332027715584/photo/1 https://twitter.com/SteveStuWill/status/1248000332027715584/...
  - goatlover 7y ago
    Except without the frames and colored lines. Lines 10 and 20 don't provide the experiences. They're just behavior. Somehow all the sensations have to be added in when looking at the world and looking at one's reaction to the world.
    - hateful 7y ago
      let experience$ = INKEY$
  - AndrewKemendo 7y ago
    Taking this further, I suppose you could consider persistence of vision [1] as analogous to consciousness. It's an artifact of the limitations of the system. [1] https://en.wikipedia.org/wiki/Persistence_of_vision https://en.wikipedia.org/wiki/Persistence_of_vision
bronlund 7y ago
That Tiphareth is the natural consequence of Geburah is ancient news. A little bit late to the party there :P
shireboy 7y ago
ELI5 "anti-correlated" here? What I envision is the temporal circuit acting like a computer clock, and the other as input/output. But "anti correlated" makes it sound like that's not the case?
- cjhveal 7y ago
  Not ELI5 exactly, but the article does a pretty good job of explaining in the first paragraph: > The default mode network (DMN) is an internally directed system that correlates with consciousness of self, and the dorsal attention network (DAT) is an externally directed system that correlates with consciousness of the environment... the DMN and DAT appear to be in a reciprocal relationship with each other such that they are not simultaneously active, i.e., they are “anticorrelated.” The "temporal circuit" the paper describes is the neural architecture that facilitates the transitions between these two networks.
  - abvdasker 7y ago
    Totally fascinating. It makes me wonder what kind of dysfunction would result from both the DMN and DAT being active at the same time, and especially what my subjective experience of that would be if it were happening to me.
    - lifty 7y ago
      I am not sure if this is accurate but intuitively, in strong psychedelic experiences it feels that both the DMN and DAT are active at the same time, which leads to, among many other things, a clearheaded view of mental processes that are hard to observe otherwise. One example would be observing emotions and how they affect your state of mind, while at the same time being totally detached from them. Some studies [1] propose that this happens because of an increase in connectivity between various parts of the brain, which could also be the thing that leads to ego dissolution. [1] https://www.cell.com/current-biology/fulltext/S0960-9822(16)30062-8 https://www.cell.com/current-biology/fulltext/S0960-9822(16)...
    - Mithriil 7y ago
stcredzero 7y ago
Language is a Virus. Consciousness is an OODA Loop. (You could write an alternative set of lyrics to the Laurie Anderson song.)
david_w 7y ago
The brain is the most complicated structure in the known universe. The probes currently available to science- fMRI and GSR - are both gross measures of cortical electrical activity. They're enough to start to explore apparent structural and (gross) electrical correlation between brain areas and (gross) alterations in "consciousness", in this case unconsciousness invoked via propofol and ketamine. Fair enough. However, it irritates me when I hear scientists loosely throw the word "consciousness" into these studies and here's why. In these studies, consciousness is always implicitly defined operationally as the electrical activity in some identified networks- DAT and DSM and front-parietal and sensory motor etc.. But the concept of consciousness has another life in philosophy where in works by people like Patricia Churchland and others, it references something more subtle- the mystery of why there should be anything we call experience at all. Experience itself doesn't seem to be necessary to the working of any machine, including our brains. We don't think our TVs have any experiences despite (being capable of) accurately representing all human visual experiences. The reason we don't think they experience what they're displaying is because we know how they work and we know there's no ghost in the machine. Adding on "experiences" to an explanation of how TVs work is gratuitous and unnecessary. But that's not the case with humans-just the opposite. Experience is absolutely foundational. Descartes tried to boil his world down to what he could know with absolute certainty and arrived at his famous "Cogito ergo sum" formulation, but actually, he skipped a step; that step is simply- "There is experience". Experience is perfectly gratuitous to any explanation of brain activity since all that activity, like an electrical storm, could take place in exactly the same way without it. We (our brains) could be, and most scientists believe are, very complicated, but purely mechanical machines. They could be exactly as they are with no more awareness- not to say feedback loops- than a blender. But that account leaves the problem of experience or consciousness completely untouched. That would be O.K. except we know we have it. The mystery of consciousness is not totally defined by questions like of "can I make you unconscious or conscious?" or "can I cause you to have this or that illusory experience by stimulating your brain?". The mystery of consciousness is why is there anything like experience at all ? So whenever I read a paper that makes some confident assertion about consciousness, it gets under my skin. It's electrical activity and perhaps human behavior and speech they are actually examining, not consciousness. I hear these papers gratingly assuming the consequent with respect to the biggest mystery there is. They are implicitly saying "this is consciousness, this pattern of electrical activity in the brain and here is what we have discovered about consciousness". That's one perspective, but to philosophers, both academic and non-academic, it's a form of punting on the real question. Consciousness is to brain science what AGI is to AI. Researchers just love to make assertions and grand predictions. Actually the correlation between the two is closer than that since strong AI claims that consciousness can be captured in a computer; Kurtzweil and his Singularity concept is in this school of thought. He and people like him claim that not only does experience arise as a direct result of brain activity but any substrate- including general purpose computer platforms- will similarly give rise to the same experiences if only they are programmed in a particular way, specifically, if the computations are functionally equivalent to the brain's computations. Are badly programmed computers therefore experiencing chaos? Well, why not? Are simpler computers, like a thermostat which "experiences" temperature changes, also somehow dimly conscious? If that seems like a straw man argument to you, you should know Marvin Minsky bought it and so do a lot of other scientists whether they realize it or not. All of this is just a non-starer to people like me. You don't get to skip a step because it keeps your theory neat or provides you the promise of immortality because you uploaded your "you" to a machine. Consciousness, understood in this way, is a genuine mystery which for now at least I don't think we have the conceptual tools to even define much less make pronouncements about.
akozak 7y ago
> Here, we conservatively use the term “unresponsiveness” instead of “unconsciousness” to allow for the possibility that covert or disconnected consciousness could occur in the absence of behavioral response. Conservatism is very wise! Given what they say in that quote, I'm very confused why they think it's justified in the intro to suggest they've identified 2 systems responsible for consciousness. Shouldn't they replace every use of the word "consciousness" with "responsiveness"? They're relying on a purely behavioral understanding of consciousness Descartes famously thought that consciousness lived in the pineal gland, and similar arguments has tended to generate some well deserved criticism from philosophers of mind. Pointing at a physical thing and saying it's the source of conscious experience should come with pretty extraordinary evidence.
- hackinthebochs 7y ago
  >They're relying on a purely behavioral understanding of consciousness They're relying on the fact that consciousness has physical manifestations in behavior. The alternative is epiphenomenalism. While it may be a philosophically interesting position, its useless scientifically and so its fair to assume consciousness has some physical artifacts in a scientific context.
  - akozak 7y ago
    I don't think we're forced to choose between behaviorism and epiphenomenalism. But my point is more internal to the paper. They make claims about the physical basis for consciousness and seem to believe they've generated evidence for it, but they also explicitly say they've only gathered evidence about responsiveness. EDIT: To be clear I'm objecting to the semantics (which I consider important), not the potential value of the research.
sebringj 7y ago
This feels right in terms how I experience things when I've had bad migraines and notice parts of my capability going away temporarily such as understanding speech or being able to read words or missing visual areas entirely. Things get jumbled or confused, all the while, I am aware of these things happening yet unable to control them. It feels like there are separate parts of me like modules that go offline but the one that is constant is the sense of "me" or the consciousness part. These episodes are few and far between but I am still thankful to have a different perspective of our bio-mechanical nature. It also makes me feel closer to my pets in the sense that awareness or consciousness doesn't correlate with cognitive ability or intellect but that is just my guess.
- sebringj 7y ago
  relating to this...it makes me very curious about Neuralink or similar tech impact on humanity once that becomes more advanced. If it is true we have these specialized processing areas while our awareness is another specialized area, it would follow that all sorts of capabilities the new tech brings would simply be incorporated and assumed just as we assume our ability to remember a name or add numbers in our head. It will be a crazy future that I hope to see.
a5ha54eha5e4 7y ago
I'll be the asshole here: this is crap. They took some weak correlations (anti-correlations whatever) between conscious brains and 'unconscious' brains induced via Ketamine. The rest of the paper is just creating new jargon for large vague regions of the brain, and tons of jump-the-shark assumptions about how they work together. Most notably, there's no mention of STDP, nor the cingulate gyrus, or any reference to the fine-structure internals of the brain.

416 points by hhs 7y ago

Man, I love seeing more research like this. My personal experience, as someone who has dealt with a variety of issues in psychiatrists' offices and rehabilitation rooms, is that a clear scientific understanding of what is actually going on under my skull provides a much firmer basis for any therapeutic approach. I'm really hoping that in my lifetime we will see connections made between the physiological elements of consciousness and the modern psychiatric plagues of depression, anxiety, and addiction that finally produce the targeted, universally effective therapies that are desperately needed.

kohtatsu 7y ago
I was recently talking to a registered psych nurse, and we got talking about Cognitive Behavioural Therapy. I believe I've been self administering a form of it for a couple years, and I summarized my understand of CBT as "moving more thinking from the amygdala to the prefrontal cortex", and she confirmed that with "in laymen's terms; yes". It's not like the fields are completely isolated, I guess is what I'm getting at with that anecdote. It's hard to go from neuroscience to psychology, but that's always being looked at. I reckon most big advancements will start coming when we start understanding the connectome more, but it's not like all advancements will come from there, and it's not like people aren't working right now to bridge neuroscience and psychology. Also I want to hang out with the laymen she does.
- rhcom2 7y ago
  Do you mind sharing your approach to how you make that shift from "amygdala to the prefrontal cortex"? Is it similar to practicing mindfulness with a focus on the now?
  - mettamage 7y ago
    No, prefrontal cortex is about planning, reasoning and inhibiting emotions (we do it all the time without realizing) among a lot of other things. Amygdala is based on reacting to fear, among other emotions. CBT gives you a toolset to ask yourself questions to understand (a) which perspective you're currently looking things from and (b) which other perspectives you could use. The 10 cognitive distortions and recognizing them is a good start. Cognitive distortions happen mostly through emotional processes (e.g. the amygdala but the whole limbic system really). Mindfulness meditation is an emotional-based approach as it mostly relates (for laymen like me) to scanning the body. Scanning the body gives marked improvements to the insular cortex. It also gives marked improvements to the PFC (the inhibition part, not the planning part). This is all written way too short and my knowledge is a bit stale on it. I used to be really into this a couple of years ago. It was during the time when I studied psychology (I even published a neuroscientific literature review :D).
    - Enginerrrd 7y ago
      I love the spirit of your response, but I feel the need to disagree a bit and elaborate about your statement: >Mindfulness meditation is an emotional-based approach as it mostly relates (for laymen like me) to scanning the body The REAL essence and power of mindfulness is becoming aware of the contents of your attention. For some reason, focusing the attention inwards on bodily somatosensory experiences tends to encourage that, but the two are not the same. Body-scanning is more a technique to help encourage the development of mindfulness rather than the end goal in itself. The reason this distinction is so important and powerful is that the brain regions which are feeding the contents of your attention are the ones that get reinforced. When you combine mindfulness with practice in redirecting your attention, it becomes an insanely powerful tool to fundamentally reshape your reality by restructuring your brain.
      - uoaei 7y ago
        Yes exactly. The "mindfulness" designation is a recursive one, where first you are mindful, then you are mindful of that which is mindful, and all the way down.
- curo 7y ago
  I'm not qualified to contest this, but I do remember a side blurb from "Principles of Neuroscience" (Kandel, Schwartz, Jessell) that said overactive mPFCs are attributed with autism and below is some more research on it. I don't think you're saying this overtly but I have seen people from the Thinking Fast & Slow crowd glorify their PFCs as arbiters of cognitive bias while forgetting that healthy social, emotional processing required integrated functioning between all neural correlates involved, including the amygdala. I would venture to guess CBT is effective because it stops overactive PFCs which is the opposite of what the nurse's guess is. But as a laymen here, I can't say one way or the other. I remember a decade or two ago, the ACC+vmPFC combo was getting a lot of praise as this balancing force between the dlPFC and the amygdala saying strong ACC+vmPFC could be the clue to healthy brains. I think the answer will always be, "hey all these parts are important. Just meditate, exercise, and eat right. And don't believe your thoughts too much (CBT)" https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5192959/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5192959/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4688328/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4688328/
  - deleted 7y ago
    [deleted]
  - fsloth 7y ago
    As a depression patient, that's more or less healed, here's my take: - In depression you can get up lost in these cognitive negative loops - One of the feedback loops is between what you feel and what you think - a bad feeling induces you to think some bad thoughts, and as those thoughts are combined with the bad feeling, they are validated as true. Now the thought is associated with a bad feeling, and one will give rise to the other , just like tinkle of the bell induced pavlov's dog to drool. But in this case the drooling of the dog can also make the bell tinkle, causing more drooling... - the amygdala response is about the bad feelings, and how the bad feelings can induce more physiological discomfort due to amygdala kicking in and doing "what it's supposed to" - now your bad feelings are superchardged as well - so, I would say it's not only about cortex or amygdala, but in depression the negative thought patterns and the physiological response can get linked into this destructive loop of continuous feedback. Hence, it does not matter that you can rationally say to yourself the bad thoughts you had are not that serious because they just launched a full scale amygdala based storm of bad feeling and anxiety - my ssri:s kind of felt like they cut out this bad loop. I felt like my cognitive self was insulated from the physiological response, giving me space to unlearn both cognitive and emotional bad habits one at a time without the disruptive loop taking control
- arminiusreturns 7y ago
  Funnily enough, many combat vet friends of mine have had the most returns from two things which both seem to affect the brain in the same manner: cannabis and CBET. On the former, I can't recall who at the moment but there is significant research that has shown the primary cause of cannabis being so well received by those with ptsd is that is reduces amygdala activity and increases pfc activity.
trub 7y ago
psychedelic plant medicine is highly effective

ta1234567890 7y ago

Sounds like the temporal circuit is acting like a clock, as in a computer chip's clock. Pretty cool. > We demonstrate that the transitions between default mode and dorsal attention networks are embedded in this temporal circuit, in which a balanced reciprocal accessibility of brain states is characteristic of consciousness. Conversely, isolation of the default mode and dorsal attention networks from the temporal circuit is associated with unresponsiveness of diverse etiologies. These findings advance the foundational understanding of the functional role of anticorrelated systems in consciousness.

naasking 7y ago

The anti-correlated behaviour of these two networks, and even their default mode vs. attention functions, reminds of the attention schema theory of consciousness [1]. Specifically, the attention schema theory posits that some constant back and forth signal switching between internal and external models of the world results in the illusion of subjective awareness, in an analogous manner to how task switching provides the illusion of parallelism on single-core CPUs. [1] https://www.frontiersin.org/articles/10.3389/fpsyg.2015.00500/full https://www.frontiersin.org/articles/10.3389/fpsyg.2015.0050...

hirundo 7y ago
So psuedo basic for the consciousness algorithm: 10 look at world 20 look at my reaction to world 30 goto 10 Which generates consciousness like frames per second generates motion. Or like the colored lines over this black and white photo generate a color image: https://twitter.com/SteveStuWill/status/1248000332027715584/photo/1 https://twitter.com/SteveStuWill/status/1248000332027715584/...
- goatlover 7y ago
  Except without the frames and colored lines. Lines 10 and 20 don't provide the experiences. They're just behavior. Somehow all the sensations have to be added in when looking at the world and looking at one's reaction to the world.
  - hateful 7y ago
    let experience$ = INKEY$
- AndrewKemendo 7y ago
  Taking this further, I suppose you could consider persistence of vision [1] as analogous to consciousness. It's an artifact of the limitations of the system. [1] https://en.wikipedia.org/wiki/Persistence_of_vision https://en.wikipedia.org/wiki/Persistence_of_vision

bronlund 7y ago

That Tiphareth is the natural consequence of Geburah is ancient news. A little bit late to the party there :P

shireboy 7y ago

ELI5 "anti-correlated" here? What I envision is the temporal circuit acting like a computer clock, and the other as input/output. But "anti correlated" makes it sound like that's not the case?

cjhveal 7y ago
Not ELI5 exactly, but the article does a pretty good job of explaining in the first paragraph: > The default mode network (DMN) is an internally directed system that correlates with consciousness of self, and the dorsal attention network (DAT) is an externally directed system that correlates with consciousness of the environment... the DMN and DAT appear to be in a reciprocal relationship with each other such that they are not simultaneously active, i.e., they are “anticorrelated.” The "temporal circuit" the paper describes is the neural architecture that facilitates the transitions between these two networks.
- abvdasker 7y ago
  Totally fascinating. It makes me wonder what kind of dysfunction would result from both the DMN and DAT being active at the same time, and especially what my subjective experience of that would be if it were happening to me.
  - lifty 7y ago
    I am not sure if this is accurate but intuitively, in strong psychedelic experiences it feels that both the DMN and DAT are active at the same time, which leads to, among many other things, a clearheaded view of mental processes that are hard to observe otherwise. One example would be observing emotions and how they affect your state of mind, while at the same time being totally detached from them. Some studies [1] propose that this happens because of an increase in connectivity between various parts of the brain, which could also be the thing that leads to ego dissolution. [1] https://www.cell.com/current-biology/fulltext/S0960-9822(16)30062-8 https://www.cell.com/current-biology/fulltext/S0960-9822(16)...
  - Mithriil 7y ago

stcredzero 7y ago

Language is a Virus. Consciousness is an OODA Loop. (You could write an alternative set of lyrics to the Laurie Anderson song.)

david_w 7y ago

The brain is the most complicated structure in the known universe. The probes currently available to science- fMRI and GSR - are both gross measures of cortical electrical activity. They're enough to start to explore apparent structural and (gross) electrical correlation between brain areas and (gross) alterations in "consciousness", in this case unconsciousness invoked via propofol and ketamine. Fair enough. However, it irritates me when I hear scientists loosely throw the word "consciousness" into these studies and here's why. In these studies, consciousness is always implicitly defined operationally as the electrical activity in some identified networks- DAT and DSM and front-parietal and sensory motor etc.. But the concept of consciousness has another life in philosophy where in works by people like Patricia Churchland and others, it references something more subtle- the mystery of why there should be anything we call experience at all. Experience itself doesn't seem to be necessary to the working of any machine, including our brains. We don't think our TVs have any experiences despite (being capable of) accurately representing all human visual experiences. The reason we don't think they experience what they're displaying is because we know how they work and we know there's no ghost in the machine. Adding on "experiences" to an explanation of how TVs work is gratuitous and unnecessary. But that's not the case with humans-just the opposite. Experience is absolutely foundational. Descartes tried to boil his world down to what he could know with absolute certainty and arrived at his famous "Cogito ergo sum" formulation, but actually, he skipped a step; that step is simply- "There is experience". Experience is perfectly gratuitous to any explanation of brain activity since all that activity, like an electrical storm, could take place in exactly the same way without it. We (our brains) could be, and most scientists believe are, very complicated, but purely mechanical machines. They could be exactly as they are with no more awareness- not to say feedback loops- than a blender. But that account leaves the problem of experience or consciousness completely untouched. That would be O.K. except we know we have it. The mystery of consciousness is not totally defined by questions like of "can I make you unconscious or conscious?" or "can I cause you to have this or that illusory experience by stimulating your brain?". The mystery of consciousness is why is there anything like experience at all ? So whenever I read a paper that makes some confident assertion about consciousness, it gets under my skin. It's electrical activity and perhaps human behavior and speech they are actually examining, not consciousness. I hear these papers gratingly assuming the consequent with respect to the biggest mystery there is. They are implicitly saying "this is consciousness, this pattern of electrical activity in the brain and here is what we have discovered about consciousness". That's one perspective, but to philosophers, both academic and non-academic, it's a form of punting on the real question. Consciousness is to brain science what AGI is to AI. Researchers just love to make assertions and grand predictions. Actually the correlation between the two is closer than that since strong AI claims that consciousness can be captured in a computer; Kurtzweil and his Singularity concept is in this school of thought. He and people like him claim that not only does experience arise as a direct result of brain activity but any substrate- including general purpose computer platforms- will similarly give rise to the same experiences if only they are programmed in a particular way, specifically, if the computations are functionally equivalent to the brain's computations. Are badly programmed computers therefore experiencing chaos? Well, why not? Are simpler computers, like a thermostat which "experiences" temperature changes, also somehow dimly conscious? If that seems like a straw man argument to you, you should know Marvin Minsky bought it and so do a lot of other scientists whether they realize it or not. All of this is just a non-starer to people like me. You don't get to skip a step because it keeps your theory neat or provides you the promise of immortality because you uploaded your "you" to a machine. Consciousness, understood in this way, is a genuine mystery which for now at least I don't think we have the conceptual tools to even define much less make pronouncements about.

akozak 7y ago

> Here, we conservatively use the term “unresponsiveness” instead of “unconsciousness” to allow for the possibility that covert or disconnected consciousness could occur in the absence of behavioral response. Conservatism is very wise! Given what they say in that quote, I'm very confused why they think it's justified in the intro to suggest they've identified 2 systems responsible for consciousness. Shouldn't they replace every use of the word "consciousness" with "responsiveness"? They're relying on a purely behavioral understanding of consciousness Descartes famously thought that consciousness lived in the pineal gland, and similar arguments has tended to generate some well deserved criticism from philosophers of mind. Pointing at a physical thing and saying it's the source of conscious experience should come with pretty extraordinary evidence.

hackinthebochs 7y ago
>They're relying on a purely behavioral understanding of consciousness They're relying on the fact that consciousness has physical manifestations in behavior. The alternative is epiphenomenalism. While it may be a philosophically interesting position, its useless scientifically and so its fair to assume consciousness has some physical artifacts in a scientific context.
- akozak 7y ago
  I don't think we're forced to choose between behaviorism and epiphenomenalism. But my point is more internal to the paper. They make claims about the physical basis for consciousness and seem to believe they've generated evidence for it, but they also explicitly say they've only gathered evidence about responsiveness. EDIT: To be clear I'm objecting to the semantics (which I consider important), not the potential value of the research.

sebringj 7y ago

This feels right in terms how I experience things when I've had bad migraines and notice parts of my capability going away temporarily such as understanding speech or being able to read words or missing visual areas entirely. Things get jumbled or confused, all the while, I am aware of these things happening yet unable to control them. It feels like there are separate parts of me like modules that go offline but the one that is constant is the sense of "me" or the consciousness part. These episodes are few and far between but I am still thankful to have a different perspective of our bio-mechanical nature. It also makes me feel closer to my pets in the sense that awareness or consciousness doesn't correlate with cognitive ability or intellect but that is just my guess.

sebringj 7y ago
relating to this...it makes me very curious about Neuralink or similar tech impact on humanity once that becomes more advanced. If it is true we have these specialized processing areas while our awareness is another specialized area, it would follow that all sorts of capabilities the new tech brings would simply be incorporated and assumed just as we assume our ability to remember a name or add numbers in our head. It will be a crazy future that I hope to see.

a5ha54eha5e4 7y ago

I'll be the asshole here: this is crap. They took some weak correlations (anti-correlations whatever) between conscious brains and 'unconscious' brains induced via Ketamine. The rest of the paper is just creating new jargon for large vague regions of the brain, and tons of jump-the-shark assumptions about how they work together. Most notably, there's no mention of STDP, nor the cingulate gyrus, or any reference to the fine-structure internals of the brain.