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Biotech Science

Spontaneous Brain Activity and Human Behavior 141

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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Spontaneous Brain Activity and Human Behavior

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  • Mind (Score:3, Insightful)

    by Cuppa 'Joe' Black ( 1000483 ) on Friday October 05, 2007 @06:56PM (#20874579)
    Your mind is not in your brain. Your brain is in your mind.
  • Maybe, but... (Score:5, Insightful)

    by DragonWriter ( 970822 ) on Friday October 05, 2007 @06:59PM (#20874603)

    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.

    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...
  • Whah? (Score:3, Insightful)

    by yali ( 209015 ) on Friday October 05, 2007 @07:05PM (#20874661)

    First paragraph of the Neuron article (which is paraphrased in Ars Technica):

    Historically, there have existed two alternate perspectives for understanding brain function (Llinas, 2001). The first conceptualizes the brain as an input-output system primarily driven by interaction with the external world. The second suggests that the brain operates on its own, intrinsically, with external factors modulating rather than determining the operation of the system. The former perspective has motivated the majority of neuroscience research, but accumulating evidence is emphasizing the importance of the latter.

    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 []:

    It is astonishing what havoc is wrought in psychology by admitting at the outset apparently innocent suppositions, that nevertheless contain a flaw. The bad consequences develop themselves later on, and are irremediable, being woven through the whole texture of the work. The notion that sensations, being the simplest things, are the first things to take up in psychology is one of these suppositions.

    The experiment may well be scientifically interesting, but not for the reason advertised.

  • Re:Mind (Score:4, Insightful)

    by BillyBlaze ( 746775 ) <> on Friday October 05, 2007 @07:09PM (#20874725)
    How can a physical entity exist inside a non-physical entity? Dualism may be a compelling philosophy for some, but lacking any evidence of violations of known physical laws in the brain, it's scientifically useless.
  • How sad (Score:4, Insightful)

    by exp(pi*sqrt(163)) ( 613870 ) on Friday October 05, 2007 @07:12PM (#20874755) Journal
    > One option it presents is that the brain is an input-output device: give it a stimulus, and it will process it and respond. The alternative view is that the brain is simply doing its own thing, and stimuli act to modulate its activity, rather than direct it.

    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?

  • by jd ( 1658 ) <> on Friday October 05, 2007 @08:20PM (#20875369) Homepage Journal
    If system A has a direct connection to external stimulus B, and system A moves to a deterministic state for any given fixed value of B, for all B, then A is a direct I/O device. (Chaotic systems are non-predictable, but they are wholly deterministic. The distinction is important.)

    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.

  • Re:Maybe, but... (Score:4, Insightful)

    by marcello_dl ( 667940 ) on Friday October 05, 2007 @08:48PM (#20875555) Homepage Journal
    > 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?

    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.
  • Re:Free will. (Score:3, Insightful)

    by EllisDees ( 268037 ) on Friday October 05, 2007 @09:00PM (#20875627)
    How so? Even when I'm sitting in a dark, silent room I can be thinking about any number of things that could be activating different areas of my brain. Even when I'm sleeping, my brain is still active even though it is receiving no sensory input. What's so hard to believe about one part of your brain stimulating another part, and so on and so on in all sorts of strange patterns?

    Or were you just joshing us? ;)
  • by Strange Ranger ( 454494 ) on Friday October 05, 2007 @11:00PM (#20876227)
    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. :)
  • Re:Mind (Score:2, Insightful)

    by Johann Public ( 542327 ) <> on Saturday October 06, 2007 @02:07AM (#20877095) Homepage
    The functioning of brain processes produces the phenomenon of mind
  • by Anne Thwacks ( 531696 ) on Saturday October 06, 2007 @05:15AM (#20877703)
    Nope - its saying that the majority of processing is not directly connected with I/O. Which means there are other tasks that handling I/O - and this comes as a surprise to who?
  • by yali ( 209015 ) on Saturday October 06, 2007 @03:48PM (#20881849)
    Your analogy to math/sociology rings false. Mathematics is not an empirical science; its relation to sociology (or any scientific field) is complementary rather than overlapping. A mathematician who works on the pure math underlying game theory is perfectly safe as long as he doesn't try to draw conclusions about human behavior. If he starts doing so, then yes, he has stepped into sociology, and his statements can and should be evaluated in light of sociological data and theory.

    In this case, these neuroscientists aren't just talking about spikes in the nervous system. They are talking about cognitive functions of the brain - by your own argument, they are trying to tackle stimulus-response processing, attention, anticipation, etc. So they are very much trying to address psychological issues. And therefore, they can and should be called out for setting up a psychological strawman.

    As I said, the narrower read of the article is scientifically interesting. Intertrial variability in behavior can be explained by left SMC activity. The controlling influence of left SMC activity can be partitioned not only into an effect of the experimentally-controlled stimuli (well-established), but also an effect of right SMC activity (which is what is new in this study). Right SMC activity is mostly independent of the experimental stimuli. They also try to demonstrate (through some indirect inferences from null significance tests) that right SMC is independent of attention or anticipation, and seem to do so with some degree of confidence.

    So why is that scientifically interesting? The authors start the article by saying there's a debate about whether spontaneous brain activity is meaningful, and they claim to be speaking to that debate. That's a lot of hot air. Instead, they should have started by saying that it has been acknowledged for at least 127 years that spontaneous mental activity (which necessarily means brain activity as well) influences behavior over and above stimulus input, and hey look, we've identified a specific manifestation of that, and for the first time demonstrated it at a neurological level of analysis. That's new and important. But it's not what they said.

"An organization dries up if you don't challenge it with growth." -- Mark Shepherd, former President and CEO of Texas Instruments