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      CommentAuthorV
    • CommentTimeJan 10th 2008 edited
     (475.1)
    Originally spotted in new scientist, but I recommend the original paper if you are actually interested in this.

    The abstract:
    The concept of universality proposes that dynamical systems with the same power law behaviors are equivalent at large scales. We test this hypothesis on the Earth's crust and the epileptic brain, and discover that power laws also govern the distributions of seizure energies and recurrence times. This robust correspondence is extended over seven statistics, including the direct and inverse Omori laws. We also verify in an animal seizure model the earthquake-driven hypothesis that power law statistics co-exist with characteristic scales, as coupling between constitutive elements increases towards the synchronization regime. These observations point to the universality of the dynamics of coupled threshold oscillators for systems even as diverse as Earth and brain and suggest a general strategy for forecasting seizures, one of neurosciences' grails.


    Though I will grant that new scientist makes it sound rather saucy:
    They both start with tiny, barely perceptible tremors that lead up to a cataclysmic climax - and now it seems that the similarities between earthquakes and epileptic seizures run deep. Seismology could even hold the key to new ways of predicting and avoiding seizures.



    Mind you, I find the connection between earthquakes moving through the topology of the earth, and seizures moving through the topology of your brain pretty sexy all on its own.

    Brain as planet. Nice.
    •  
      CommentAuthorAriana
    • CommentTimeJan 10th 2008
     (475.2)
    Nice find, V. That's lovely.
    •  
      CommentAuthorobliterati
    • CommentTimeJan 10th 2008
     (475.3)
    I'm having a time out until I can learn some manners.
    That is unbelievably interesting. I have to get a subscription now!
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      CommentAuthortim12s
    • CommentTimeJan 10th 2008
     (475.4)
    But does the Earth come 'round with a splitting headache, people acting like its a five-year old, and feeling distinctly retarded for several days afterwards?

    Interesting, a case of as above, so below, but Epilepsy is sooo not sexy.
  1.  (475.5)
    For some reason my last comment never posted - and I'm lateish for work, so I'll be quick.

    There are around 10 types of epilepsy, so how does this model account for them?

    Does it also account for the post-ictal stage of epilepsy, where there is drowsiness and confusion and sometimes violence against unsuspecting ambulance crews?

    (Not that we mind the violence so much, as it's just part of the illness, so not the fault of the patient).

    Hold up - a quick scan of the paper says that the patients were maintained on *reduced dose* of anti-epileptics?! Also they only look at one type of epilepsy...

    Seems dodgy to me, I'll have to give the paper a proper read in a bit.
    • CommentAuthortmofee
    • CommentTimeJan 11th 2008
     (475.6)
    I have a friend who is the opposite, she's confused before not after. Afterwards she says she feels like she has a hangover, and usually a bitten tongue..
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      CommentAuthorV
    • CommentTimeJan 11th 2008 edited
     (475.7)
    @Reynolds - I don't believe they mean to model the entirety of epilepsy; my understanding is that they are just talking about early warning systems.

    I wouldn't blame the new scientist description (or mine) on the paper though. I don't think it is dodgy. As near as I can tell they are pretty upfront about what their model applies to.

    They look at transiently disabling seizures in "human subjects with mesial temporal and frontal lobe pharmaco-resistant epilepsies".
    (Well, and they look at rats too.)
    They are looking at the mathematics of the patterns when there are "sudden, aperiodic, potentially damaging oscillations of morphology" starting from a discrete region.
    So, of course earthquakes don't help us understand drowsiness and confusion in later stages or anything else like that. This is purely at the level of the mathematical descriptions of the dynamics.
    I think it is pretty amazing to see the same mathematical patterns moving through brain and earth, but I don't think it is a detailed and complete model of an entire set of neurological disorder.

    I hadn't meant to suggest otherwise, so sorry if I did.

    Incidentally, why do you object to the reduced dose of anti-epileptics? I don't know enough about treating patients with epilepsy to see what you're pointing out. Are you objecting to them not having a full dose or to them having any dose? I'm guessing the dosage just has to do with needing to measure seizures but not wanting patients to be at any greater discomfort or risk than necessary to do that. But like I said, I know very little about actually treating patients with epilepsy.
  2.  (475.8)
    Incidentally, why do you object to the reduced dose of anti-epileptics?

    Well, as said I've only skim-read it but the thing about reduced doses of anti-epileptic meds jumped out at me. Here is my problem with the study as a healthcare provider.

    Anti-epileptics are given to patients in order to reduce the number of seizures. This is a good thing.
    Seizures are inherently dangerous for reasons such as hypoxia (lack of oxygen to the tisues of the body, including the brain), also the more physical effects like snapping your bones with alternating muscle contractions, dislocations and bashing yourself against something harder than you.
    To reduce the medications, and put patients at risk of these effects, in order to study mathematics seems a bit unethical to me. That's all.

    Often the people that I see having, or having just had a seizure have just had their medication reviewed/reduced or changed by a primary healthcare provider (GP) and while there are perfectly good reasons to 'fiddle' with meds (reduction of side effects for example) the though of doing this in order to *cause* seizures just rubs me up the wrong way.

    Anyhow - now I have a chance to read the study properly, all the above may be moot...
  3.  (475.9)
    On second thoughts - trying to read it has broken my brain, but it *looks* like the EEG measurements of epileptic patients is from another study. Which hopefully was cleared by an ethics committee.

    I think that my hackles were raised by it not being formatted like a medical study, which is the only studies I have even the faintest idea of how to read.

    (Not too sure about their possible explanation for Status fits either - but again, the maths is a few grades above my payscale...)