11 ms·

Consciousness is supported by near-critical slow cortical electrodynamics

228 points by hsnewman 5y ago

mach1ne 5y ago
I find that it's disingenuous to propose attributes of consciousness when consciousness hasn't even properly been defined. There is not a shred of evidence that something like our concept of consciousness even exists.
- juliangamble 5y ago
  Disagree. As a science, Psychology is largely based on self-reporting.
  - mach1ne 5y ago
    And incidentially the field has a huge problem with pseudoscience, with studies that are not replicable, lying with statistics, theories which aren't falsifiable... The problem with consciousness is that the only evidence it exists is that individuals claim to experience it, without even really defining what it is they experience. This "evidence" has a much simpler explanation than the existence of an almost-magical consciousness. It's not that there can't be something like consciousness, but there is currently nothing to indicate this.
- martopix 5y ago
  Consciousness here means being in a conscious state, i.e. not sleeping, not fainted, not in an altered psychedelic state. It is clearly defined. Regrettably the word consciousness also refers to the "hard-problem of consciousness" thing.
superkuh 5y ago
Pretty cool. I am surprised that low frequency dynamics are so strongly associated with reports of aware conciousnes states given that the high frequency 40 Hz activity of cortico-thalamo-cortical loops are necessary (if not sufficient) for consciousness as well. I'd put my money on the low frequency dynamics being a downstream effect from the cessation of the ~40 Hz cortico-thalamo-cortical loops under anesthesia. I'd also like it if they had included a gas anesthetic along with the receptor mediated anesthetics.
drran 5y ago
Event loop.
inpdx 5y ago
Can anyone ELI5 this?
- colechristensen 5y ago
  Eh, not really. It's hard to describe features of chaos / nonlinear dynamics simply. There are features of chaotic systems that undergo phase changes from one type of behavior to another. Think a signal on one side of the transition to look like a pure sine wave and on the other side of the transition to look like purely random white noise. What these guys are reporting is that they found a parameter, a signal they can measure in brains that seems to correlate with consciousness. When the signal is right up near the edge of this kind of chaotic phase transition, the subject is conscious, when nowhere near the phase transition, you aren't. So they have a way to sort of measure and quantify consciousness and perhaps even control it a little by measuring and doing things to manipulate this signal. It might be sort of like an OPEN sign in a store, just a signal that happens to reflect consciousness, or this brain wave behavior might be a fundamental part of consciousness and higher thinking. It all seems quite interesting. Projecting guesses out for this is that chaotic dynamics are a fundamental part of how our brains, especially at the highest levels work. One would guess given this evidence and other things that one of the things that makes consciousness possible is a complex system kept balanced at a knife edge of a certain kind of chaotic phase transition. It's also the kind of thing that can open a backdoor for free will in a deterministic universe, your brain in this chaotic state might behave deterministically but the actual state would never be knowable with enough precision to predict the outcome of inputs for any amount of time (butterfly effect).
  - verisimi 5y ago
    "Think a signal on one side of the transition to look like a pure sine wave and on the other side of the transition to look like purely random white noise." This reminds me of something Rupert Sheldrake says is possible - that consciousness is 'off-site', that the body is more of a radio receptor.
    - robbedpeter 5y ago
deleted 5y ago
[deleted]
netsharc 5y ago
It's a weird feeling to realize how we're all just hardware, and it might be possible to wake up someone who's "brain dead"/vegetative by LSD (the paper mentions how psychedelics affect this cortical electrodynamics, and as this old article[1] mentions the LSD). Imagine someone flipping a switch (in the future where tech to control the electrodynamics exists) and you're awake and aware of your surroundings again. [1] https://therooster.com/blog/scientists-want-to-give-psychedelics-to-people-in-vegetative-states https://therooster.com/blog/scientists-want-to-give-psychede...
- awb 5y ago
  > The idea of using LSD as a treatment has floated around the Internet for decades. There are rumors — totally unconfirmed — that an astronomical dose of LSD — "a quarter of a vial," or 25 hits — woke up an unresponsive dude and, after a few days, he was able to speak. It's entirely possible those stories are true. “Unresponsive dude” lol. Interesting descriptor. It doesn’t sound like anyone has tried it yet.
  - unfocussed_mike 5y ago
    > “Unresponsive dude” lol. Interesting descriptor. Yeah, well, you know, that's just, like, your opinion, man.
- tpfl 5y ago
- hackinthebochs 5y ago
  Ambien has been known to rouse people out of a coma and help with other brain disorders: https://www.verywellhealth.com/ambien-for-coma-dystonia-and-brain-injuries-4149544 https://www.verywellhealth.com/ambien-for-coma-dystonia-and-...
- jodrellblank 5y ago
  > “The first report of a zolpidem awakening came from South Africa, in 1999. A patient named Louis Viljoen, who, three years before, was declared vegetative after he was hit by a truck, had taken to clawing at his mattress during the night. Thinking he was suffering from insomnia, his family doctor suggested zolpidem to help him sleep. But 20 minutes after his mother ground the tablet up and fed it to him through a straw, Viljoen began to stir. His eyes, which normally wandered the room, vacant and unfocused, flickered with the light of consciousness. And then he began to talk (his first words were “Hello, Mummy”), and move (he could control his limbs and facial muscles). A few hours later he became unresponsive. But the next day, and for many days after that, zolpidem revived him, a few hours at a time” - https://www.nytimes.com/2011/12/04/magazine/can-ambien-wake-minimally-conscious.html https://www.nytimes.com/2011/12/04/magazine/can-ambien-wake-...
ghostly_s 5y ago
What does "a critical point or phase transition [of the] electrodynamics of the cortex" mean? Electricity doesn't have "phases" AFAIK (well there's two/three-phase power but I don't think that's what they're talking about).
- mlyle 5y ago
  https://en.wikipedia.org/wiki/Phase_transition https://en.wikipedia.org/wiki/Phase_transition https://en.wikipedia.org/wiki/Critical_exponent https://en.wikipedia.org/wiki/Critical_exponent The concept of phase transition is broader than the phases of matter.
  - ghostly_s 5y ago
    Interesting, though the only example I see listed in that article that's not a change in the physical properties of matter is the ferromagnetic<=>paramagnetic phases.
    - mlyle 5y ago
      Lots of the list are changes of physical properties of matter (e.g. breaking of physics symmetries in the cooling universe)... that are not conventional matter phase transitions between e.g. liquid and gas.
    - colechristensen 5y ago
      One that isn’t a matter it’s convection currents in a closed vessel between two plates of different temperatures. At low differentials there’s no convection just conduction, as you raise the temperature difference you get a stable single circulation loop which is well behaved, continue further and you get a tempest of circulations coming and going in an entirely unpredictable manner. There are distinct phase transitions between each of these states. Another one is a forced double pendulum. With just a little periodic force they swing gently back and forth, with a lot they do constant crazy unpredictable loops around each other.
    - tzs 5y ago
unfocussed_mike 5y ago
"This book deals with epiphenomenalism, which has to do with consciousness as a mere accessory of physiological processes whose presence or absence... makes no difference... whatever are you doing?"
geijoenr 5y ago
This appears to be an indication of a new phenomenon correlated to criticality in cortical electrodynamics, that also correlates to consciousness as we understand it. It looks to me is a huge step, because even the result is so far empirical, the first step to understand anything is being able to measure it.
markhahn 5y ago
This strikes me as totally unsurprising. How could it be otherwise? It's basically saying that a brain normally operates in an interesting dynamical mode: not chaotic, and not very regular. Wow? If it were chaotic, we wouldn't have coherent or consistent behavior at any scale. If overly regular, we'd be incredibly dull and unable to respond to the environment. You could do this with a computer. If your signals coming from the computer are either too regular or too unexpected, then it's probably broken. This sort of thing might be useful diagnostically, but doesn't really provide us with greater understanding...
- tomrod 5y ago
  A captured signal may represent a pathway for intervention, a cause, or a margin to address. Imagine if we found that schizophrenia or other potentially debilitating mental health condition were 99.9999% correlated with this signal being weak or strong. That would be telling. If only for diagnosis, and possibly as a cause. EDIT: a word - "would be telling"
- civilized 5y ago
  Welcome to the world of Complex Systems research. Complex Systems guy: we just showed a system operates in a critical state scale-free phase transition and its key statistics have a power law distribution! Everyone: okay, so? CS guy: I dunno? That's what our discipline does. It tells you things are in critical states with power laws. So now you know that...
  - jquery 5y ago
    I think this research is super interesting, and it's disappointing such a blaze, dismissive comment is at the top. Cosmologists: we literally took a picture of a black hole! Someone: So? I already knew they existed. Besides, it's not a picture of a black hole, it's just the ring around the black hole. yawn Cosmologists: oh... sorry for wasting your time.
    - cjbgkagh 5y ago
      I was far more interested in the algorithms they used than the actual picture of the black hole.
ffhhj 5y ago
So, consciousness is like a big casino in which the brain builds a bets for different theories, and this chaos measured come from all the dice throwing.
tpfl 5y ago
PaulHoule 5y ago
If this is true then there are two different ways to be unconscious.
- jamiek88 5y ago
  And that makes sense. Unconscious as in knocked out and unconscious as in someone complete unaware but eyes open, moving around on bath salts.
- s1artibartfast 5y ago
  Im not sure that is true, unless you count being dead as unconscious. Sleep could also be an excited incoherent state.
bidaewnl 5y ago
Materialism died out over a 100 years ago and has been repeatedly proven through hundreds of experiments from labs throughout the world to be total junk science. Why do people feel the need to continuously push this fake science?
- PeterisP 5y ago
  > has been repeatedly proven through hundreds of experiments from labs throughout the world to be total junk science. Point to one, please.
deleted 5y ago
[deleted]

228 points by hsnewman 5y ago

I find that it's disingenuous to propose attributes of consciousness when consciousness hasn't even properly been defined. There is not a shred of evidence that something like our concept of consciousness even exists.

juliangamble 5y ago
Disagree. As a science, Psychology is largely based on self-reporting.
- mach1ne 5y ago
  And incidentially the field has a huge problem with pseudoscience, with studies that are not replicable, lying with statistics, theories which aren't falsifiable... The problem with consciousness is that the only evidence it exists is that individuals claim to experience it, without even really defining what it is they experience. This "evidence" has a much simpler explanation than the existence of an almost-magical consciousness. It's not that there can't be something like consciousness, but there is currently nothing to indicate this.
martopix 5y ago
Consciousness here means being in a conscious state, i.e. not sleeping, not fainted, not in an altered psychedelic state. It is clearly defined. Regrettably the word consciousness also refers to the "hard-problem of consciousness" thing.

superkuh 5y ago

Pretty cool. I am surprised that low frequency dynamics are so strongly associated with reports of aware conciousnes states given that the high frequency 40 Hz activity of cortico-thalamo-cortical loops are necessary (if not sufficient) for consciousness as well. I'd put my money on the low frequency dynamics being a downstream effect from the cessation of the ~40 Hz cortico-thalamo-cortical loops under anesthesia. I'd also like it if they had included a gas anesthetic along with the receptor mediated anesthetics.

drran 5y ago

Event loop.

inpdx 5y ago

Can anyone ELI5 this?

colechristensen 5y ago
Eh, not really. It's hard to describe features of chaos / nonlinear dynamics simply. There are features of chaotic systems that undergo phase changes from one type of behavior to another. Think a signal on one side of the transition to look like a pure sine wave and on the other side of the transition to look like purely random white noise. What these guys are reporting is that they found a parameter, a signal they can measure in brains that seems to correlate with consciousness. When the signal is right up near the edge of this kind of chaotic phase transition, the subject is conscious, when nowhere near the phase transition, you aren't. So they have a way to sort of measure and quantify consciousness and perhaps even control it a little by measuring and doing things to manipulate this signal. It might be sort of like an OPEN sign in a store, just a signal that happens to reflect consciousness, or this brain wave behavior might be a fundamental part of consciousness and higher thinking. It all seems quite interesting. Projecting guesses out for this is that chaotic dynamics are a fundamental part of how our brains, especially at the highest levels work. One would guess given this evidence and other things that one of the things that makes consciousness possible is a complex system kept balanced at a knife edge of a certain kind of chaotic phase transition. It's also the kind of thing that can open a backdoor for free will in a deterministic universe, your brain in this chaotic state might behave deterministically but the actual state would never be knowable with enough precision to predict the outcome of inputs for any amount of time (butterfly effect).
- verisimi 5y ago
  "Think a signal on one side of the transition to look like a pure sine wave and on the other side of the transition to look like purely random white noise." This reminds me of something Rupert Sheldrake says is possible - that consciousness is 'off-site', that the body is more of a radio receptor.
  - robbedpeter 5y ago

deleted 5y ago

[deleted]

netsharc 5y ago

It's a weird feeling to realize how we're all just hardware, and it might be possible to wake up someone who's "brain dead"/vegetative by LSD (the paper mentions how psychedelics affect this cortical electrodynamics, and as this old article[1] mentions the LSD). Imagine someone flipping a switch (in the future where tech to control the electrodynamics exists) and you're awake and aware of your surroundings again. [1] https://therooster.com/blog/scientists-want-to-give-psychedelics-to-people-in-vegetative-states https://therooster.com/blog/scientists-want-to-give-psychede...

awb 5y ago
> The idea of using LSD as a treatment has floated around the Internet for decades. There are rumors — totally unconfirmed — that an astronomical dose of LSD — "a quarter of a vial," or 25 hits — woke up an unresponsive dude and, after a few days, he was able to speak. It's entirely possible those stories are true. “Unresponsive dude” lol. Interesting descriptor. It doesn’t sound like anyone has tried it yet.
- unfocussed_mike 5y ago
  > “Unresponsive dude” lol. Interesting descriptor. Yeah, well, you know, that's just, like, your opinion, man.
tpfl 5y ago
hackinthebochs 5y ago
Ambien has been known to rouse people out of a coma and help with other brain disorders: https://www.verywellhealth.com/ambien-for-coma-dystonia-and-brain-injuries-4149544 https://www.verywellhealth.com/ambien-for-coma-dystonia-and-...
jodrellblank 5y ago
> “The first report of a zolpidem awakening came from South Africa, in 1999. A patient named Louis Viljoen, who, three years before, was declared vegetative after he was hit by a truck, had taken to clawing at his mattress during the night. Thinking he was suffering from insomnia, his family doctor suggested zolpidem to help him sleep. But 20 minutes after his mother ground the tablet up and fed it to him through a straw, Viljoen began to stir. His eyes, which normally wandered the room, vacant and unfocused, flickered with the light of consciousness. And then he began to talk (his first words were “Hello, Mummy”), and move (he could control his limbs and facial muscles). A few hours later he became unresponsive. But the next day, and for many days after that, zolpidem revived him, a few hours at a time” - https://www.nytimes.com/2011/12/04/magazine/can-ambien-wake-minimally-conscious.html https://www.nytimes.com/2011/12/04/magazine/can-ambien-wake-...

ghostly_s 5y ago

What does "a critical point or phase transition [of the] electrodynamics of the cortex" mean? Electricity doesn't have "phases" AFAIK (well there's two/three-phase power but I don't think that's what they're talking about).

mlyle 5y ago
https://en.wikipedia.org/wiki/Phase_transition https://en.wikipedia.org/wiki/Phase_transition https://en.wikipedia.org/wiki/Critical_exponent https://en.wikipedia.org/wiki/Critical_exponent The concept of phase transition is broader than the phases of matter.
- ghostly_s 5y ago
  Interesting, though the only example I see listed in that article that's not a change in the physical properties of matter is the ferromagnetic<=>paramagnetic phases.
  - mlyle 5y ago
    Lots of the list are changes of physical properties of matter (e.g. breaking of physics symmetries in the cooling universe)... that are not conventional matter phase transitions between e.g. liquid and gas.
  - colechristensen 5y ago
    One that isn’t a matter it’s convection currents in a closed vessel between two plates of different temperatures. At low differentials there’s no convection just conduction, as you raise the temperature difference you get a stable single circulation loop which is well behaved, continue further and you get a tempest of circulations coming and going in an entirely unpredictable manner. There are distinct phase transitions between each of these states. Another one is a forced double pendulum. With just a little periodic force they swing gently back and forth, with a lot they do constant crazy unpredictable loops around each other.
  - tzs 5y ago

unfocussed_mike 5y ago

"This book deals with epiphenomenalism, which has to do with consciousness as a mere accessory of physiological processes whose presence or absence... makes no difference... whatever are you doing?"

geijoenr 5y ago

This appears to be an indication of a new phenomenon correlated to criticality in cortical electrodynamics, that also correlates to consciousness as we understand it. It looks to me is a huge step, because even the result is so far empirical, the first step to understand anything is being able to measure it.

markhahn 5y ago

This strikes me as totally unsurprising. How could it be otherwise? It's basically saying that a brain normally operates in an interesting dynamical mode: not chaotic, and not very regular. Wow? If it were chaotic, we wouldn't have coherent or consistent behavior at any scale. If overly regular, we'd be incredibly dull and unable to respond to the environment. You could do this with a computer. If your signals coming from the computer are either too regular or too unexpected, then it's probably broken. This sort of thing might be useful diagnostically, but doesn't really provide us with greater understanding...

tomrod 5y ago
A captured signal may represent a pathway for intervention, a cause, or a margin to address. Imagine if we found that schizophrenia or other potentially debilitating mental health condition were 99.9999% correlated with this signal being weak or strong. That would be telling. If only for diagnosis, and possibly as a cause. EDIT: a word - "would be telling"
civilized 5y ago
Welcome to the world of Complex Systems research. Complex Systems guy: we just showed a system operates in a critical state scale-free phase transition and its key statistics have a power law distribution! Everyone: okay, so? CS guy: I dunno? That's what our discipline does. It tells you things are in critical states with power laws. So now you know that...
- jquery 5y ago
  I think this research is super interesting, and it's disappointing such a blaze, dismissive comment is at the top. Cosmologists: we literally took a picture of a black hole! Someone: So? I already knew they existed. Besides, it's not a picture of a black hole, it's just the ring around the black hole. yawn Cosmologists: oh... sorry for wasting your time.
  - cjbgkagh 5y ago
    I was far more interested in the algorithms they used than the actual picture of the black hole.

ffhhj 5y ago

So, consciousness is like a big casino in which the brain builds a bets for different theories, and this chaos measured come from all the dice throwing.

tpfl 5y ago

PaulHoule 5y ago

If this is true then there are two different ways to be unconscious.

jamiek88 5y ago
And that makes sense. Unconscious as in knocked out and unconscious as in someone complete unaware but eyes open, moving around on bath salts.
s1artibartfast 5y ago
Im not sure that is true, unless you count being dead as unconscious. Sleep could also be an excited incoherent state.

bidaewnl 5y ago

Materialism died out over a 100 years ago and has been repeatedly proven through hundreds of experiments from labs throughout the world to be total junk science. Why do people feel the need to continuously push this fake science?

PeterisP 5y ago
> has been repeatedly proven through hundreds of experiments from labs throughout the world to be total junk science. Point to one, please.

deleted 5y ago

[deleted]