Slashdot Mirror
Spontaneous Brain Activity and Human Behavior
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.'"
Sadly, they are usually inversely proportional.
Maybe it's this constant variability (Ha! Parse that!) which accounts for my never actually getting first post.
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.
Your mind is not in your brain. Your brain is in your mind.
Technically, murder-suicide does not violate the golden rule.
an article summarizing an interesting and perhaps controversial paper which finds links between spontaneous brain activity and human behavior.
This study would have been way more exciting if they had used goatse to elicit the neural response.
The theory of relativity doesn't work right in Arkansas.
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...
1. Early in the morning when I'm fresh
2. When I'm really really tired or slightly drunk and think I'm funny.
Also tend to come up with humourous ideas when I'm under pressure and mind is racing through problems -- I'll think, "Hey what if this were like so..." and the inevitable side-tracking happens. The Bob only knows how many funny things I'm come up with over the years and remember bugger all about any more. Good to know the well doesn't run dry though, there's always a fresh batch of insanity right around the corner to inspire another joke.
I think my brain patterns were trained on early issues of MAD and Monty Python.
A feeling of having made the same mistake before: Deja Foobar
So basically what this paper is saying is that everybody has a random number generator running in his head to slightly alter his action from what everybody else would do.
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:
The experiment may well be scientifically interesting, but not for the reason advertised.
this is not about a fugue state or tourette's or about some novel variation on "the devil made me do it!" style legal defense
it has to with tiny variations, not large coordinated sustained activities
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
men for years have tried to explain to their wives what made them sleep with that other woman, but NO MORE! We now have a physiological excuse! "You see, dear, I was actually overcome by a spontaneous yet organized brain activity, perhaps spurred on by two or more guinnesses, perhaps not."
I wish my coworkers would show some spontaneous brain activity.
This work speaks against our (faulty, I claim) conceptualization of the brain as an information processing device, implementing some analysis algorithms a-la David Marr. Instead, think of the brain as a device whose function is to predict the immediate future. Since the environment is probably dynamic, it would be silly to stay put and wait for cues to indicate the changes outside. It is far more effective to try and guess ahead, go-with-the-flow, constantly stay in flux (some tai-chi overtones here, I admit). Hence spontaneous activity. Experimenters try to create an artificially-controlled environment which is nothing like what we have evolved for, and hence have hard time explaining these results. Does this make sense to you, fellow Slashdotters?
Do it yourself, because no one else will do it yourself. [beta blockade 10-17 Feb]
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?
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
About time some hard evidence confirmed what us duelists have known all along. Finally the old dogma of reductionism can be laid to rest.
Remember, it works both ways.
You are being MICROattacked, from various angles, in a SOFT manner.
Wow. I belive that trying to understand the human mind is about the most important thing anybody can be doing.
Everything I know about my brain is mediated knowledge. Other people (lots of other people whom I never met) with specialized equipment (which I will never get to use) have been studying the brain for generations. They have formed many elaborate models about how it works, what it does, and how it accounts for human behavior. Then, they shared these models with the world (including me).
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.
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 randomness can exist.)
If system A has no direct connection to ANY external stimulus, but is rather operating solely off an internal model which may or may not ever get updated from an external source, then A not only exists independent of whether B exists, but cannot ever establish by any test as to whether B exists. Within normal operating conditions, A can be treated as though it were in a pocket universe, independent and isolated from the universe in which any B may exist, and should therefore be regarded as an isolated system.
The brain may be an I/O device, a chaotic system, or an isolated system. Arguments have been given for each. One thing it is NOT is a modulated system. That possibility does not really exist. The moment the connection becomes indirect, then you run into the limitations of knowledge and certainty. If you cannot distinguish between modulation by an external cause and a change of state due to internal causes, then you can't ever know if the external exists at all. It might all be a figment of your imagination. You can't conduct any test to establish otherwise, as any test which is definitely not a figment of your imagination cannot alter the external and anything that can definitely alter the external cannot be provably not a figment of your imagination.
As for Linux, the inability to determine a future state is NOT the same as the future state being non-deterministic. You cannot produce a quantum OS using Turing logic. You CAN produce an isolated system, and some research into strong AI and machine reasoning goes in this direction, but it hasn't been terribly useful so far.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
The idea of neurons that are spontaneously active, in the absence of synaptic input, is not in the least bit novel. The "canonical" neurons like spinal cord motoneurons and hippocampal pyramidal cells, striatal medium spinies, etc, certainly remain silent until they receive sufficient afferent input. However, there are tons of neurons that are perfectly content to spike away, all by themselves in a tissue slice, with all synaptic input blocked. Giant cholinergic interneurons in the striatum, dopamine cells of the substantia nigra, subthalamic nucleus, globus pallidus cells... all of these will fire rhythmically in the absence of any input. You can even isolate "networks" of them on a culture plate, and the network will fire in a rhythmic, antisynchronous bursting pattern, again in the absence of any external input.
Just putting that out there... spontaneous activity in the brain isn't nearly as "gee whiz" as it sounds. It's just part of the machinery of the brain.
Excellent news. This may help to change more of the philosophical underpinnings of some of the various branches of science. Physics already is confronting some of these changes. I don't dare speak of them in this crowd yet, but they are coming. Offtopic comment: Leave the Tags alone!
"Time is nothing; timing is everything."
I have dreams that usually don't have any connection to events at the time I'm having them. (well I'm sleeping, the stuff in the dream is spontaneous "experience" that has nothing to do with current sensory imput) and the dreams don't seem to have much to do with whatever else is going on in my waking life either. Not literally, not symbolically, not even emotionally. It's just stuff going on, and I can give it meaning (tempting, it's in our brains to ascribe meaning to experienceor recognize it as simplly stuff going on.
And actually, as I think about it, remembered sleep dreams are fairly rare. Day-to-day experience is largely a dream. A fairly tiresome one, as it turns out, but a dream nonetheless.
What did they expect to happen in their experimeents? Did they expect people to simply have no brain activity?
If a brain gets new sensory input, it's going to take some time to process that information, no? When you learn something new, it often takes a lot of time to think things through, and you can continue making new connections for quite some time without any new external inputs. This happens when we're sleeping, too, so maybe this happens under anesthesia as well.
I'm not quite sure what the hell they're thinking here. Are they trying to allude to a soul?
It could be modulated, just we don't have terms or hard evidence yet of the particles involved. If you assume some sort of external modulation as a premise, it helps explain occasional "paranormal" events that people experience, but are not 100% reproducible in the lab. It might also explain the lack of normal radio wave communications in the universe, why we aren't receiving any that we recognize, despite the odds being heavily in favor of more life elsewhere. They just might have fixated more on understanding and using these particles of "sort-of matter, sort-of energy" if I can invent a term for something we have no good name for yet.
And this helps explain this random spontaneous activity, because it wouldn't be "random"
which really makes ya stop and think on that one
According to some, consciousness and self-awareness arise out of Strange Loops
:)
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". 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.
Operator, give me the number for 911!
So you're saying that some people actually think even when they're not receiving sensory input, and that their thinking might influence future behavior? What will they think of next?
(Of course, looking at the media and politicians, perhaps people do come to the conclusion that all humans are simple input/output response systems.)
Another theory is that the "spontaneous brain activity" is normally suppressed, and it exists because it allows for a faster reaction time if necessary.
The brain's complexity is still too great for us to model in exacting detail. While the conceptual jumps between the functioning of a neuron to the subtleties of human behavior are small, they are nonetheless present (and numerous). It is faith, and nothing more, that inclines you to say that we (the scientists) "know" that the mind is nothing more than the brain's software.
Don't get me wrong, I love science. It's fruits are in evidence and I study neuroscience as a hobby. However, I do not love arrogance, and I especially do not love the very unscientific practice of drawing conclusions that are outside the scope of the available evidence.
Our present models of human behavior make some useful predictions, though they are not perfectly accurate and they have a huge gap: the models do not express our common experience of consciousness. The word "conscious" is often used (in a scientific sense) to mean little more than "responsive." However, the connotations that impregnate this word did not come about by accident. The mystery of consciousness, and most importantly its staunchly indeterministic and non-mechanical nature, is a moment-by-moment immediate reality for all humans.
Some of us have played conceptual games with ourselves in order to rationalize away its existence, because of its theoretically problematic nature. And who am I to say that some of us may not actually be philosophical zombies (i.e., soft machines that perfectly mimic conscious beings)? Be that as it may, my consciousness is far more real to me than anything I could ever read or study via objective experimentation. Any model that excludes it is simply incomplete, and any model that defines it as nothing more than emergent phenomena of deterministic, mechanical processes is simply incorrect.
I am not a religious man. I do not embrace mythology as reality, even if it comes from a scientist.
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 going.
Faster! Faster! Faster would be better!
I can dream too, but it takes generations for even the most obvious paradigm shift to start to inform even the wider academic populace. Communicating a genuinely new underlying physics is going to present even more obstacles than a new life science paradigm. Even though they're a century old, no other theoretical field has yet drawn a serious metaphor from GR or QM.
-- Our systemic servants do not good masters make.
Well, the summary of the article says nothing of the kind (as usual, I'm tempted to say).
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 acting subjects) in a particular area are strongly related to the variations you see in resting state activity.
So, half of the blood flow fluctations (0.74 ^ 2) in a brain with a minimum of activity seems to return when the brain has a very simple task. Not really a big deal.
Caveat: I haven't read the full paper (I'm at home right now).
Could this activity be somehow different in and a cause or symptom of Autism?
Also, could this activity itself be modulated in a co-ordinated manner thru carefully patterned sensory input ? Could explain the supposed effects of music, mantras, chants etc. on mood
The resting brain is not silent, but exhibits organized fluctuations in neuronal activity even in the absence of tasks or stimuli. This intrinsic brain activity persists during task performance and contributes to variability in evoked brain responses. What is unknown is if this intrinsic activity also contributes to variability in behavior.
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.
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 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.
How is this offtopic? There needs to be an Unfunny mod to cover poorly-executed "jokes" that are nonetheless on-topic.
Maybe that would cut down on the "I'm trying to be funny, look!" first-50-comment spam that has ruined discussion at slashdot.
You're just wrong, hippie. It's easy, with surgery or lately with transcranial magnetics, to demonstrate that the mind is a software function of the brain, in a manner similar to cracking smart cards (interfere with them physically to interfere with their running). You underestimate the progress of science during and after WWII.
You are a neuroscientist sympathetic to the Chalmers school?
No offense, does that have anything to do with your anonymity? I am just curious about the landscape in today's neuroscience research community.
I shall patent me. and then Charge to much for licensing.
That will solves all the worlds problem.
http://abstractionphysics.net/pmwiki/index.php
On a more serious note, this
Not funny, doesn't even make sense.
Anything that is not a direct consequece of some immediate sensory input must be a consequence of some internal state. Such internal state can very well be just a "delayed sensory input" like you said. But is't just a philosopycal distinction at the end.
...
Pretty much anything that is not too simple has plenty of internal states. You can still boot and run a computer without keyboard, mouse and network card attached, and the same goes for a simple cell or a clock.
of course you have to supply the energy that the system needs to run, but that's another story
We learn from history that we learn nothing from history - Tom Veneziano
By the way, there is a much more mundane explanation of the similarity in brain activity: subjects got bored in both tasks. Pressing buttons is not really the most challenging task. Therefore, they might simply be sleeping with their eyes open the same way they do in the condition where they're not supposed to think of anything. I'd like to see an experimental design that can rule that out...
Does this mean we _aren't_ mere biomechanical machines and actually _do_ posses more attributes than the physical ones we can see, touch, and dissect?
-Wes
there is nothing spontaneous and nothing unknown about the human brain. Keep researching!
?
You mean the brain is active even while I'm asleep?
I wouldn't have imagined that even in my wildest dreams...
We're all born with nothing.
If you die in debt, you're ahead.
I would mod you up if I could.
Am I the only one thinking of the word "brainfart" here? Spontaneous Brainfart, it's simple as that :)
The human brain uses 100% of itself 100% of the time. The content of thoughts, perceptions and memories are processed by collections of cells called Hebbian Cellular Assemblies. The content of these, and the binding of them, are alway active.
I'm glad to see someone has finally replicated Donald O. Hebb's 1939 work.
Next, hopefully someone will discovery neurons.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
And since we know the mind does it, the brain (almost) has to; it seems that people here for the most part get that. What's surprising is that the field doesn't; while it's true that neuroscientists won't deny that the human brain does rumination disconnected from current inputs, neither does it receive much attention (speaking as a postdoc in the field). Brain science is important, useful, and fun, but it's not yet a complete field; people here have noted the conspicuous absence of an explanation for consciousness. The field really hasn't worked hard enough on it yet to make me think that one doesn't exist. I think we'll get that explanation of consciousness only after brain science starts paying more attention to "spontaneous activity," that is, thinking.