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Spontaneous Brain Activity and Human Behavior
Posted by
Zonk
on Fri Oct 05, 2007 05:41 PM
from the argh-me-precious-brains dept.
from the argh-me-precious-brains dept.
Dr. Eggman writes "Ars Technica is featuring an article summarizing an interesting and perhaps controversial paper which finds links between spontaneous brain activity and human behavior. Spontaneous, yet organized brain activity has been observed without stimulation and even in humans under anesthesia. This paper attempts to link this activity to the observed variability of human performance in even simple, repeated tasks, hoping to establish a new avenue of research into alternative brain processing theories. 'The subtraction provided a much cleaner connection between the button press and brain activity in the left SMC. Once spontaneous activity was accounted for, noise was down by 60 percent, and the signal to noise ratio in the experiments doubled. Putting this another way, spontaneous activity accounted for about 60 percent of the variation between tests. The authors say that these results show that spontaneous brain activity is more than simply a physiological artifact; it helps account for some of the variability in human behavior. In that sense, they argue for a greater acceptance of the view that our brain may have some intrinsic activity that's somewhat independent of sensory input.'"
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Uh Yeah.. (Score:5, Funny)
This has been a postulate of mine for a while. It's the only rational explanation for me thinking about sex every 5 seconds - with our without sensory input.
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Mind (Score:3, Insightful)
Re:Mind (Score:4, Insightful)
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I have never seen my brain (Score:4, Interesting)
My experience of my mind, however is immediate. I sense it directly. I didn't become aware of it by being told it was there, I became aware of it by feeling it.
So, in a very concrete sense, my mind is more real to me than my brain. I have experienced my mind directly, whereas I have only heard about my brain second-hand. What sense does it make for me to believe that something which I experience moment-by-moment isn't real because of its incompatibilities between some idea of how things work which I have only experienced, and can only ever experience, second-hand?
Scientists model our experience of reality. These models are not perfect; they have gaps. We shouldn't respond to these gaps by pretending that reality has them too. We should simply recognize them as gaps and continue to study what we can.
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Re: (Score:2)
http://dictionary.reference.com/browse/in [reference.com]
in: (...)
2. (used to indicate inclusion within something abstract or immaterial): in politics; in the autumn.
> lacking any evidence of violations of known physical laws in the brain, it's scientifically useless.
This is a tautology. Introducing concepts that are beyond what can be scientifically experienced is useless from a scientific POV, like e.g. the concept of color is useless from the point
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On the other hand, the concept of color is absolutely critical from the point of view of counting from one to tan.
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Oh noes, not the Church of Tantology again!
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Ever since man discovered that the physical world is 100% controlled by the laws of nature. The neuronal activity in your brain and everything that your brain and rest of your body does is caused by the laws of physics, not by little green aliens living in an invisible 5th dimension that don't contrubute (dualism) to those laws.
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Ahh, the joys of pot.
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How did we get that info? Well, we used the senses we have at our disposal...but those are mediated in the brain. And they do not always reflect what we think of as "objective" reality. This is not about subjectivity; this is about our experience being distant from actual events, like how chemical data can be transmitted as either taste or as
Re:Mind (Score:4, Interesting)
Let's go to a movie. We'll sit in a comfy chair, and watch Indiana Jones dodge boulders. What happens?
1. Usually, a person enters a state that can be described as focused monomania (just as Hypnosis can be described). For an hour and a half, they focus on the film so that they are unaware of anything beyond the edges of the screen. They believe the events shown are every bit as real as real life until the film is over. They jump when Ripley opens a hatch and the ship's cat pops out. They cringe when Michael Myers swings an axe. They get aroused when
2. A conscious person, typically of normal mental health, has had an out of the body experience lasting typically 90 minutes or so. The other things in life that can allegedly normally cause such an effect aren't present. There's no chemical disturbance of the brain (as from a hallucinogen). There's no physical disturbance (as from a blow to the head). There's no build up of fatigue toxins (as is sometimes used to explain sleep related mental effects). There's nothing but images, images which in the hands of a skilled artist can be so compelling that we choose to become entangled, enthralled, enraptured.
3. Now describe it in evolutionary terms: We observe some members of a species that has just developed many of its unique brain functions over the last million years. They have lived for 99.999% of that time in small groups typically numbering less than 30. The single most common predator for that entire time was members of other small groups of humans, who typically were just as virulently cannibalistic as we observe today in chimpanzees. Without any of the causes we normally consider to cause a brain dis-function, these members of that species have become totally oblivious to large numbers of strangers, not of their tribe, they have made a deliberate, determined effort to become so, and to stay in that state for an extended time.
4. The mystery is, why, after doing that once, do humans not realize what they have done, run out of movie theaters screaming, and never return?
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testing methods (Score:3, Funny)
This study would have been way more exciting if they had used goatse to elicit the neural response.
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Maybe, but... (Score:5, Insightful)
While that may be the case, how does one rule out that the possibility that the activity is a delayed reaction to sensory input, rather than an immediate one? Even assuming that the anesthetization is really enough to rule out the possibility of it being the result of immediate sensory input...
Re:Maybe, but... (Score:4, Insightful)
Might be, but if you are trying to force a "mechanical" model of the brain (which I don't assume you're doing) think about this: a degree of randomness helps avoiding stalling or deadlock situation (think about old toy cars with stupid algorithms to avoid obstacles that get stuck hitting the same spot over and over, or how ethernet devices cope with packet collisions).
On another perspective, the one of behavior, predictable patterns are weaker than randomized one, because the external world is subjected to chaotic changes and because you will never catch by surprise a competitor who's studying you. So a degree of randomness is likely an evolutionary advantage.
Besides, if there were a delay it would be quite variable not to have been yet detected as such by all but superficial analysis, so a more general theory of something random inside the brain would hold.
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It can also be selected against evolution-wise. If you had predictable patterns, a predator of comparable evolution-al tendencies would evolve to exploit such behaviors.
Another theory (Score:2)
Whah? (Score:3, Insightful)
First paragraph of the Neuron article (which is paraphrased in Ars Technica):
Does anybody who has spent more than 2 minutes thinking about the human mind really believe that first argument? Somebody should introduce these guys to William James [yorku.ca]:
The experiment may well be scientifically interesting, but not for the reason advertised.
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Well it's way simpler and much more deterministic. Perhaps a good first try, but, like you, I think it's not even wrong [wikipedia.org]. But I'm not a neuroscientist.....
It is an over-simplification (Score:4, Interesting)
In the sense that it is an oversimplification, useful to establish things in a word-count limited introduction, but whose primary role seems to be to lead laypeople to grotesque and frightening misapprehensions, no, neuroscientists don't believe that first argument.
It is unquestionable that there is neural activity in the absence of sensory stimuli or motor response. It is also known that this activity is not unstructured but correlated across the neuronal population (though the significance of this fact is a point of dispute). Nor does anyone assume that this activity does not have the ability to influence the response of an organism -- neuronal activity is neuronal activity.
At the same time, the paramount task of the nervous system is to process the environment around the organism and respond to it appropriately. To be successful in the natural selection sense, you cannot ignore pain, mating signals, fire, loud noises, sudden movements, etc., and when something comes up, you must be able to formulate and implement a strategy which can actually deal with the situation that stimulus describes. Sensory experience is a huge part of neural activity, and if deprived of it long enough -- so that the only activity is the spontaneous activity mentioned above -- the brain enters a degenerate state. Or, to put it another way, you go insane.
The nervous system, then, is a massively complex system which has a baseline pattern of activity, is receiving constant input from a variety of sensory organs (even when you close your eyes, or plug your ears, you receive input from them; it's just meaningless), all of which is being modulated by "supervisory systems" (e.g, the dopaminergic and serotonergic systems) that control meta-response properties such as attention, anticipation, learning, expectation, and so on. The debate can be reduced to two issues. The first is: once you have accounted for stimulus-driven activity and the effects of the higher-order supervisory systems, does the baseline activity contribute any significant fraction of the organism's final response? And if so, is the baseline activity no more than the muddled-together echo of past stimulus-driven activity rattling around the recurrent network that is the brain and can thus be regarded as simply random noise, or is it meaningful in its own right?
The paper in question [neuron.org] tries to address the first of these questions. Their results seem to demonstrate that a large fraction of the inter-trial variability in a motor task cannot be explained by known modulating factors such as attention, and thus can be attributed primarily to the baseline activity. Thus, baseline activity would appear to be a major influence on response. The second question remains open, and it is really the core of the issue. These results, however, go a long way towards making it a pressing issue.
The experiment may well be scientifically interesting, but not for the reason advertised.
The experiment is scientifically interesting, and for exactly the reasons advertised. There is a fundamental difference between neuroscience and psychology. One studies the operation of the nervous system, and the other studies the nature of the human mind. The basic element of study of neuroscience is spikes, of which you are never aware; psychology interests itself in thoughts, which (from the perspective of a neuroscientist) we can't even meaningfully define, let alone measure. Perhaps one day we might be able to unite the two, but at this point, a criticism of neuroscience based on psychological principles is no more well-founded than lambasting the mathematics of game theory because it runs afoul of sociological thought.
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In this case, these neuroscie
caveat (Score:2)
it has to with tiny variations, not large coordinated sustained activities
Bah (Score:5, Funny)
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Rules of the Office
1. The boss's jokes are always funny.
2. When in doubt, see rule 1
Are you certain you want your co-workers (or are these cow-workers?) to be funny?
I worked with someone once who was silly at the most inappropriate of times. I finally hit him (just a tap) in the shoulder and insisted he be serious. I regretted hitting him, but not because he didn't deserve it.
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I got the joke. But I've just gotten out of a horrible end-of-week meeting, so I was forced to write this by Higher Powers.
How sad (Score:4, Insightful)
Oh my God, this is so stupid. I bet people really argue about this.
Put it this way: does Linux respond to stimuli or do its own thing? Is there any experiment that could help us decide? Two people could know the entire Linux source code back to front and inside out, and the source of every application running on it, and still disagree over this stupid question. Don't these people have real and meaningful phenomena to investigate?
How sad indeed (Score:2)
Wow. I belive that trying to understand the human mind is about the most important thing anybody can be doing.
Seems an easy question to answer. (Score:3, Insightful)
If system A has a direct connection to external stimulus B, and system A moves to a non-deterministic state for at least one value of B, then A is a quantum device. (Quantum systems are the only physical systems in which true ran
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That's true, but I don't see why you conclude that such a system can't exist. Our brains are in a constant state of uncertainty, weighing imperfect sensory data and imperfect memories, holding contradictory possibilities in mind while waiting for further evidence, often having to make decisions b
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Oh my God, this is so stupid. I bet people really argue about this.
It's stupid, but not because it's a non-question, it's stupid because it's a stupid question.
The brain doesn't have a Wake-on-LAN function - it is always on.
The question is like asking d
Tin Foil Hat (Score:2)
Stuck in a Strange Loop (Score:5, Insightful)
I think, therefore I am.
I realize I am, therefore I think.
But after than I'm a broken record!
Horribly simplistic to keep the post short:
Without some "spontaneous activity" injected into the strange loop that is a self-aware entity, might we not get stuck in the loop, and end up being less cognizant than a fruit fly?
Someone with a knowledge of real-world AI can flog me, but you CAN program a computer to be self-aware. It patches itself, reports crashes in it's own log, recognizes intrusions (hopefully). But without that bit of "spontaneous activity" the system can never gain an outside perspective. It can never "unask the question" [wikipedia.org]. So it's just as dumb as a Bach fugue playing itself on a player piano.
To sum up, it's Self Referentiality PLUS this "spontaneous activity" that is at the very core of sentience.
At least that's how I understand it.
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wow! (Score:5, Funny)
(Of course, looking at the media and politicians, perhaps people do come to the conclusion that all humans are simple input/output response systems.)
Misunderstood, of course (Score:2)
In some fMRI studies (I'm a post-doc in the field), the brain resting state is studied. Now, if you know what fMRI actually measures, you'll know that that means the blood flow through the brain while there is a minimum of external stimuli (plus the task to try to think of nothing, which is quite hard). So all this study claims is that some of the variability you see in normal fMRI studies (those that have stimuli and a
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I don't think you can safely pass that off as a minor little clause in your point - The same problem this FP seems to make.
Of course we have "spontaneous brain activity" that influences our performance on certain tasks. Most of us call that "thinking", preferably about the problem, but also quite possibly about lunch or that cute tech's short skirt or about why the FSM lets good pasta get overcooked.
This seems like a non-article. No one s
What next? (Score:2)
In follow-up research these scientists will investigate if there is any correlation between the loud humming noise cars make when they move and the wheels rotating.
Its Alive... uh err, I'm alive, I'M ALIVE (Score:2)
I shall patent me. and then Charge to much for licensing.
That will solves all the worlds problem.
http://abstractionphysics.net/pmwiki/index.php [abstractionphysics.net]
On a more serious note, this
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Our whole modern world is an artifically controlled environment that is nothing like what we have evolved for.
The only thing that's dynamic about my experience at the moment is the banner ads.
You there! (Score:2, Funny)
Push your chair slowly away from the desk (use your legs). Disconnect the power cord to the computer (the black rubbery thing that is poking out of the wall).
Find the stairs - go UP them.
Find a door - go OUT the door. Keep doing this until you determine that you are out-of-doors (hint: no more roof).
Look around, walk a bit. Careful of the cars. Watch out for women - they're much more dangerous in real life.
Keep goi
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Or were you just joshing us?
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Having said this, nothing at all is "random". Everything abides by causality at some physical level; you cannot escape it, and there is also no reason to fear it. The free-will vs determinism debate is pointless. Science can only accept reason.
Lead time (Score:2)
Re:Random Number Generator (Score:4, Insightful)
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