Network theory sheds new light on origins of consciousness

March 11, 2015 by Melanie Moran
The black dots correspond to the 264 areas of the cerebral cortex that the researchers probed, and the lines correspond to the increased strength of the functional connections between each of these brain areas when subjects consciously perceive the target. The "hotter" colors are associated with stronger connections. This figure illustrates that awareness of the target corresponds to widespread increase in the strength of functional connections (Credit: Marois / Godwin).

Where in your brain do you exist? Is your awareness of the world around you and of yourself as an individual the result of specific, focused changes in your brain, or does that awareness come from a broad network of neural activity? How does your brain produce awareness?

Vanderbilt University researchers took a significant step toward answering these longstanding questions with a recent imaging study, in which they discovered global changes in how brain areas communicate with one another during awareness. Their findings, which were published March 9 in the Proceedings of the National Academy of Sciences, challenge previous theories that hypothesized much more restricted changes were responsible for producing awareness.

"Identifying the fingerprints of consciousness in humans would be a significant advancement for basic and medical research, let alone its philosophical implications on the underpinnings of the human experience," said René Marois, professor and chair of psychology at Vanderbilt University and senior author of the study. "Many of the cognitive deficits observed in various neurological diseases may ultimately stem from changes in how information is communicated throughout the brain."

Using , a branch of mathematics concerned with explaining the interactive links between members of a complex network, such as social networks or flight routes, the researchers aimed to characterize how connections between the various parts of the brain were related to awareness.

"With graph theory, one can ask questions about how efficiently the transportation networks in the United States and Europe are connected via transportation hubs like LaGuardia Airport in New York," Douglass Godwin, graduate student and lead author on the research, said. "We can ask those same questions about brain networks and hubs of neural communication."

Modern theories of the neural basis of consciousness fall generally into two camps: focal and global. Focal theories contend there are specific areas of the brain that are critical for generating consciousness, while global theories argue consciousness arises from large-scale brain changes in activity. This study applied graph theory analysis to adjudicate between these theories.

The researchers recruited 24 members of the university community to participate in a functional magnetic resonance imaging (fMRI) experiment. While in the fMRI scanner, participants were asked to detect a disk that was briefly flashed on a screen. In each trial, participants responded whether they were able to detect the target disk and how much confidence they had in their answer. Experimenters then compared the results of the high-confidence trials during which the target was detected to the trials when it was missed by participants. These were treated as "aware" and "unaware" trials, respectively.

Comparison of aware and unaware trials using conventional fMRI analyses that assess the amplitude of brain activity showed a pattern of results typical of similar studies, with only a few areas of the brain showing more activity during detection of the target than when participants missed seeing it. The present study, however, was interested not simply in what regions might be more activated with awareness, but how they communicate with one another.

Unlike the focal results seen using more conventional analysis methods, the results via this network approach pointed toward a different conclusion. No one area or network of areas of the brain stood out as particularly more connected during awareness of the target; the whole brain appeared to become functionally more connected following reports of awareness.

"We know there are numerous brain networks that control distinct cognitive functions such as attention, language and control, with each node of a network densely interconnected with other nodes of the same network, but not with other networks," Marois said. "Consciousness appears to break down the modularity of these networks, as we observed a broad increase in functional connectivity between these networks with ."

The research suggests that consciousness is likely a product of this widespread communication, and that we can only report things that we have seen once they are being represented in the brain in this manner. Thus, no one part of the brain is truly the "seat of the soul," as René Descartes once wrote in a hypothesis about the pineal gland, but rather, consciousness appears to be an emergent property of how information that needs to be acted upon gets propagated throughout the brain.

"We take for granted how unified our experience of the world is. We don't experience separate visual and auditory worlds, it's all integrated into a single conscious experience," Godwin said. "This widespread cross-network communication makes sense as a mechanism by which consciousness gets integrated into that singular world."

Explore further: Scientists find 'hidden brain signatures' of consciousness in vegetative state patients

More information: Breakdown of the brain's functional network modularity with awareness, Douglass Godwin, DOI: 10.1073/pnas.1414466112

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SusejDog
2.5 / 5 (2) Mar 11, 2015
Summarized for the impatient:

The research suggests that consciousness is likely a product of this widespread communication [among numerous brain networks], and that we can only report things that we have seen once they are being represented in the brain in this manner. Thus, no one part of the brain is truly the "seat of the soul," as René Descartes once wrote in a hypothesis about the pineal gland, but rather, consciousness appears to be an emergent property of how information that needs to be acted upon gets propagated throughout the brain.


Basically it's likely emergent. But only a wishful thinker would expect anything else.
24volts
2 / 5 (4) Mar 11, 2015
I wonder if that chart would look much the same or radically different if they used that girl that only has a thin layer of brain tissue up against her skull with the rest filled with water that was found out about a few years ago during a medical exam.
Moebius
3.3 / 5 (3) Mar 12, 2015
Brilliant study and hypotheses. I would have guessed my consciousness stems from about 6 cells in the left anterior lobe of my right nut, How do people come up with dumb theories like the one that was disproved? Pretty obvious which is correct or at least I guessed right. Don't see any logic whatsoever to think consciousness comes from one small part of the brain. At least not for some people.
thingumbobesquire
1 / 5 (1) Mar 12, 2015
In other words consciousness can be explained as information age gobbledygook?
nigel_reading
not rated yet Mar 12, 2015
"Consciousness appears to break down the modularity of these networks, as we observed a broad increase in functional connectivity between these networks with awareness."
Universality in action: the quantum superposition of Orch OR as a Phi-IIT swarm cloud.
This "non-local" entangled quantum state from the E8 of Lisi up to the microtubule level - the Orch OR of Hameroff & Penrose is analogically, optimally resonated up in a holographic and fractal manner to the hyper-connected modularised and integrated, irreducible classical Phi-IIT Constructal state of Tononi and Bejan via the Asynsis geometries that unite them all.
https://asynsis.w...il-2014/
Ceon
3 / 5 (2) Mar 12, 2015
Consciousness has so far been completely out of the reach of science. The only way we can observe consciousness is by directing our own mind towards our own consciousness. I suspect it might be easier to discover the connection between physical form and consciousness by studying simpler lifeforms. Everything that lives has a consciousness, the consciousness is no different between a primitive lifeform like an insect or an ameoba and a (relatively) complex lifeform like humans... it is the mind that the consciousness observes that is different. I suspect that consciousness is something like an fundamental element of the universe, that consciousness and energy are two sides of the same coin, but of course that is beyond my observations. Unfortunately most people are very far from understanding what consciousness is, and the ideas suggested in this article demonstrate that. The mind emerges from the brain, but the consciousness that observes that mind, does not. Consciousness = Life.
russell_russell
not rated yet Mar 12, 2015
Where in your brain do you exist? Is your awareness of the world around you and of yourself as an individual the result of specific, focused changes in your brain, or does that awareness come from a broad network of neural activity? How does your brain produce awareness?


In the order of being asked:

1.) Where storage (memory) has taken place.
2.) Awareness is not "the result of specific, focused changes in your brain"
Awareness comes from retrieval of memory stored. (No specific, focused changes are occurring in your brain. You are retrieving information stored when you for example open your eyes from sleep. This is pattern-matched with what you last saw before falling asleep.
If pattern matching occurs (seeing the same thing before and after sleep) pathways to this pattern matching are strengthen.
3.) The same way an anesthesiologist takes and restores awareness is how awareness is "produced".

http://medicalxpr...ain.html
russell_russell
1 / 5 (1) Mar 12, 2015
For awareness emergence is neither necessary nor sufficient.
More than one neuron is sufficient and necessary for awareness.
http://ask.metafi...st-brain

To support that thesis a two neuron brained organism is needed.
Rotifers have 150-200 neurons - an order of magnitude too large.
The search continues.
russell_russell
1 / 5 (1) Mar 12, 2015
...Thus, no one part of the brain is truly the "seat of the soul," as René Descartes once wrote in a hypothesis [...]but rather, consciousness appears to be an emergent property of how information that needs to be acted upon gets propagated throughout the brain.


Levels of consciousness are directly proportional to the retrieval of memory (information) in response to any external stimulus harboring the potential to match existing neuronal patterns of memory. That is and those are not an emergent properties.
hugo_ten_dam
4.5 / 5 (2) Mar 13, 2015
russel_russell: it's your word against theirs...
russell_russell
1 / 5 (1) Mar 13, 2015
@hugo
The only point of disagreement was emergence.
Here an attempted explanation:

Since the existence of the universe (where emergence of properties can be asserted) stars formed.
All stars, their birth, their death, their evolutions, their compositions for all time are all governed by properties already in existence.

Consciousness is governed by properties already in existence.
Consciousness does not emerge anew for every human ever born.
(There's no evolution in that)

If I state consciousness is a state of condensed matter I will be flamed out of existence.
Too holy are the eons of dogma embracing the immaterial existence of consciousness.
russell_russell
1 / 5 (1) Mar 13, 2015
information adheres to the postulated principles of conservation. This prohibits emergence..
Consciousness controls channel capacity (of information). You have flow (of information)

...consciousness appears to be a [...] property of how information that needs to be acted upon gets propagated throughout the brain.


All I did was delete one word from the original quote (emergent).
That was all that was needed so I can continue to strengthen their support for the same research we both pursue.
Tangent2
not rated yet Mar 13, 2015
...consciousness appears to be a [...] property of how information that needs to be acted upon gets propagated throughout the brain.


This doesn't explain the reason as to why consciousness is a result of the information process. If the signals from my eyes needs to be processed by the brain, does this denote consciousness? If a CPU instruction is awaiting to be processed by the CPU, does this denote consciousness? And lastly, the brain/consciousness does nothing to address the issue of out of body or near death experiences where individuals have returned to the body with information that would have been impossible to gather (such as a show on the hospital roof) if consciousness was restricted to the brain.
Tangent2
not rated yet Mar 13, 2015
Let's take it one step further. What does this say about the double slit experiment, in which the particle/wave duality has been found to be the result of a consciousness observing the experiment or not? A phenomenon of the neural network does not explain the observer effect in quantum physics, otherwise we could argue that the results of the experiment are all in our head, but that is not the case.
russell_russell
1 / 5 (1) Mar 13, 2015
"If the signals from my eyes needs to be processed by the brain, does this denote consciousness?" - T.

Yes.
This "denotes" a need for consciousness.
Memory is a part of consciousness - no memory, no consciousness..
.

"If a CPU instruction is awaiting to be processed by the CPU, does this denote consciousness?" - T.

No.
CPU instruction is not an external signal independent from the CPU.
Pocket calculators lack the human senses human use as input.
Most sources of input being external sources for humans.
Pocket calculators lack the physical storage of information humans use.

What does this say about the double slit experiment, in which the particle/wave duality has been found to be the result of a consciousness observing the experiment or not?

Nothing.
Particle/wave duality has not been found to be the result of a consciousness observing anything anywhere. Where in the world did you get this?

cont...
russell_russell
not rated yet Mar 13, 2015
cont....

"A phenomenon of the neural network does not explain the observer effect in quantum physics"

This is true. The Zeno Quantum Effect needs no human observer. So no neural network will ever explain the Zeno Quantum Effect.

."...otherwise we could argue that the results of the experiment are all in our head, but that is not the case."

No one is arguing this. And no truer words are spoken with:
"...that is not the case". And for good measure - That is truly not the case.

Case closed.
russell_russell
3 / 5 (2) Mar 13, 2015
Consciousness is not restricted to the brain.
Not in the sense you convey.

The medical community is gearing up to transplant a human head to a body other than the owner's body soon.
This means at least you can transplant consciousness to another body.
There is no reason to stop there - you will see human brain transplants in your lifetime.
Tangent2
not rated yet Mar 16, 2015

What does this say about the double slit experiment, in which the particle/wave duality has been found to be the result of a consciousness observing the experiment or not?

Nothing.
Particle/wave duality has not been found to be the result of a consciousness observing anything anywhere. Where in the world did you get this?


"The Invariant Set Postulate appears to reconcile Einstein's view that quantum mechanics is incomplete, with the Copenhagen interpretation that the observer plays a vital role in defining the very concept of reality. Hence, consistent with Einstein's view, quantum theory is incomplete since it is blind to the intricate structure of the invariant set. Yet consistent with the Copenhagen interpretation, the invariant set is in part characterized by the experiments that humans perform on it, which is to say that experimenters do indeed play a key role in defining states of physical reality."

http://phys.org/n...980.html
russell_russell
not rated yet Mar 17, 2015
Yes.
You defeated your own argument.
Consciousness is physical.

Unfortunately you are confusing the physical with reality.

Do you want me to rate you? You are wrong. You are at least trying.
Unfortunately you asserted reality:
the concept that the universe exists with well-defined properties, independent of what we choose to observe and measure.

russell_russell
not rated yet Mar 17, 2015
...quantum mechanics is ignorant of the intricate structure of the invariant set which determines the notion of reality.


Read more at: http://phys.org/n...html#jCp

This is pure rubbish.
The Quantum Zero Effort will keep the cat permanently alive.
Here Quantum Mechanics determines the "notion" of reality.

I am starting to feel sad for you. I refuse to rate you.
yvchawla
not rated yet Mar 18, 2015
Feeling and naming is the sign of being alive, of being conscious. Senses see, touch, listen and so on, breathing in and out is going on, there is memory and imagination and thoughts arising in the mind. Anger, fear, anxiety, happiness are the expressions of Life to keep the mind alive. This is the format of Life. Can one see that there is nothing beyond this? Thought can refer to anything. It can name anything, describe anything. It can not know its own source. It can not know from where it is arising. Any reference about its source will be a thought. One is at the end of the mind.
https://sites.goo...-of-life
russell_russell
not rated yet Mar 19, 2015
You have not provided science. You provide claims without evidence. There is a label for this:
Realism. Realism asserts objective reality.
Science does fine without this assumption. Science progresses without this assumption.
Your learning curve is impossible to bring up to par when comments and web sites like yours ignores science.
The entire site of your link ignores science.

Here is a "fundamental expression":
Science can not uphold realism.
You can uphold realism. Without the science. There is no reason to rate the nonscientific.
gettingwell
not rated yet Mar 21, 2015
Did they find "compelling evidence" related to "How the brain begets conscious awareness?"

Let's begin with the "conscious" part of the conscious awareness goal. The researchers ignored the evolutionary bases of human consciousness. They were biased toward "global theories argue consciousness arises from large-scale brain changes in activity."

Let's examine the "awareness" part of the conscious awareness goal. The study's subject selection criteria and experiment equated visual perception with awareness, and excluded the contributions of other senses and methods of awareness.

Would it follow from the study's methodology that blind people cannot be consciously aware?

http://t.co/26p0FxpSVs
russell_russell
not rated yet Mar 21, 2015
...experiment equated visual perception with awareness, and excluded the contributions of other senses and methods of awareness. - gw


This argumentative platform fails from the premise. No valid conclusions can be drawn from the premise. Questions arising from the premise are meaningless. I can not indulge your questions from a false premise platform.

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