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Speldosa's Achievements


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  1. Yes, I admit I took it a little far there. Could you specify what you mean with a control or processing function?
  2. Ok. But still. Is this the question we are supposed to debate in this thread? I seriously don't understand what TS is meaning when s/he states that s/he thinks there is "some spirituality that cant be explain in science". That is, what the heck are we debating?
  3. So according to your definition, 90% of the brain would have to be totaly silent (that is, without any activity going on at all) for someone to say that you're only using 10% of your brain?
  4. I still don't understand the question. What are we supposed to debate? Whether the brain operates in such a way that its output can be predicted?
  5. So if you would like to sit through boring power point presentations for hours and hours; Sign up today! I stopped going to conferences a while ago. I find them to be mostly rubbish and waste of time anyway. With that said, I hope that this conference will turn out good for those who participate!
  6. @insane_alien: I'm still waiting for a definition of what it means when a part of the brain, or when a specific neuron, is in use. What does it mean to be using (over a certain quite long time interval) the whole brain? That activity above baseline flows through each area at some point in time? What if that activity isn't manifested in any overt behavior or conscious thoughts? Was it still being used then? What I have problems is that when you're saying that you use 100% of the brain, you're just throwing in a number, just as when you're saying that you only use 10% of the brain, without really defining what the heck you mean by that number. The problem with the 10% statement isn't, in my opinion, the number itself, but rather that it's a nonsense statement from the beginning unless you're really specifying what you're talking about. You can't debunk it by replacing it with some other number. @omgwyther: The uploader, jlvincent, who appears to be the author of the papers associated with this video states as an answer to the very first comment to that video that it is based on fMRI (Q: "where data come from? electroencephalography? fnmr?" A: "fMRI"). Further, the papers being referred to in the description of the video are both on BOLD-signals, that is, fMRI. Also, since the activity is mapped on an actual model (although flattened out) of the cortex, rather than on a model of a head, one can be pretty sure that the data comes from fMRI because of the spatial uncertainty that comes inherent with the EEG-method. That is, if this data would have been acquired through the use of EEG, it would have been bullshit. You can't specify where the signal comes from with this much accuracy (in the movie, you can even see how activity disappears behind some sulci from time to time). In an fMRI measurement you usually get voxel not more than a couple of millimeters wide.
  7. I don't think the argument will get any better by me looking at the other links. Note, that I do not defend the 10% hypothesis, however, I think that the 100% hypothesis is equally dumb.
  8. From the first link iNow posted: What data were used to come up with the number - 10%? Does this mean that you would be just fine if 90% of your brain was removed? If the average human brain weighs 1,400 grams (about 3 lb) and 90% of it was removed, that would leave 140 grams (about 0.3 lb) of brain tissue. That's about the size of a sheep's brain. It is well known that damage to a relatively small area of the brain, such as that caused by a stroke, may cause devastating disabilities. Certain neurological disorders, such as Parkinson's Disease, also affect only specific areas of the brain. The damage caused by these conditions is far less than damage to 90% of the brain. I find this to be a terrible argument. If one says that you're only using 10% of the brain (a statement that clearly needs more clarification; c.f. my earlier post) that doesn't imply that all brain matter being used is concentrated in only one part of the brain. Therefore, it could be fully consistent to say that you only use 10% of your brain and still that you would be handicapped if you removed any specific part of it. Further, the author states: Perhaps when people use the 10% brain statement, they mean that only one out of every ten nerve cells is essential or used at any one time? How would such a measurement be made? Even if neurons are not firing action potentials, they may still be receiving signals from other neurons. I find it funny that the author questions the possibility of measuring this, yet he concludes his article with "We use 100% of our brains". Well, how the heck did you measure that?
  9. Well, since this sequence is created from a fMRI scan, it is really the concentration of oxygen from the blood we are looking at, which has not been shown to be directly correlated with electrical activity. Further, what we are looking at is where the amount of oxygen is significantly higher than in the rest of the brain. That is, even if we assume a direct correlation between brain activity and blood flow, this visual presentation only shows where the strength of the activity deviates from the baseline. That an area of the brain is blue doesn't mean that nothing is going on there. We could for example in theory have a brain with uniform activity everywhere. This brain wouldn't show any activation in the fMRI at all (unless you have two conditions, in which one of them, the brain is much more quiet than in the other...Then you could light up the whole freakin brain. However, that would only show that the activity was higher in one of the conditions.). Also, I don't see where you get that 10% to 30% number from. It isn't obvious to me.
  10. This survey seems to be for people living in the UK, right? Otherwise the question whether you're british, irish or of other white background pretty strange. Maybe you should specify this somewhere.
  11. Could you please provide some good source to how the moon behaviorally affects behavior in some animals?
  12. Well, first of all. I wouldn't place the brain in a pool of blood, but rather in something equivalent to cerebrospinal fluid which the brain normally is surrounded by. As you can see in the Wikipedia-article I linked to, the cerebrospinal fluid has four functions: 1. Buoyancy: The actual mass of the human brain is about 1400 grams; however the net weight of the brain suspended in the CSF is equivalent to a mass of 25 grams.[7] The brain therefore exists in neutral buoyancy, which allows the brain to maintain its density without being impaired by its own weight, which would cut off blood supply and kill neurons in the lower sections without CSF.[8] 2. Protection: CSF protects the brain tissue from injury when jolted or hit. In certain situations such as auto accidents or sports injuries, the CSF cannot protect the brain from forced contact with the skull case, causing hemorrhaging, brain damage, and sometimes death.[9] 3. Chemical stability: CSF flows throughout the inner ventricular system in the brain and is absorbed back into the bloodstream, rinsing the metabolic waste from the central nervous system through the blood-brain barrier. This allows for homeostatic regulation of the distribution of neuroendocrine factors, to which slight changes can cause problems or damage to the nervous system. For example, high glycine concentration disrupts temperature and blood pressure control, and high CSF pH causes dizziness and syncope.[10] 4. Prevention of brain ischemia: The prevention of brain ischemia is made by decreasing the amount of CSF in the limited space inside the skull. This decreases total intracranial pressure and facilitates blood perfusion. Now, we can do without point number 2 since the brain is going to lay still in a jar, but we really need to fulfill all the other criteria's. Also, the fluid have to be renewed somehow and go through the usual cycle inside the brain. Also, we need some form of replacement for the heart and the lungs to pump oxygenated blood into the brain and to take care of blood coming back from the brain. Without these actions, the brain would certainty die pretty much immediately. Now, let's say that we could fulfill these basic things. Would the brain be able to survive? Well, not necessarily, if we with survival mean ongoing meaningful activity, which is a pretty good definition. First of all, the brain wouldn't get any stimulation from outside. That is, the eyes, the ears, the tounge, yeah, all of your senses, wouldn't generate any kind of structural input at all, but rather some kind of noisy input, if any input at all would be generated. Further, the brain wouldn't get it's usual chemical input from the body, making it go all out of balance. All this would probably create havoc inside the brain and even if you in the end would be able to maintain some kind of activity, which isn't certain, the activity would probably not represent anything meaningful.
  13. I guess you're referring to the following paragraph in the Scientific American article (if not, please correct me): The myth's durability, Gordon says, stems from people's conceptions about their own brains: they see their own shortcomings as evidence of the existence of untapped gray matter. This is a false assumption. What is correct, however, is that at certain moments in anyone's life, such as when we are simply at rest and thinking, we may be using only 10 percent of our brains. Now. There are two problems with using this as a source that we're using 10 percent of our brain at any given time. First of all, it's just at statement by some guy. There is no further reference to any scientific study. Second, he's not stating that it's correct that we're using ten percent of our brain at any given time, but rather that it's correct that we may use ten percent of our brain at any given time. That is a huge difference. That's like saying that at any given time point lightning might strike somewhere on the earth rather than at any given time point lightning does strike somewhere on the earth. This would be true both in a world where lightning only struck once and a world where lightning struck several times a second (as I believe is the case in our world). Merged post follows: Consecutive posts mergedIf we're going to talk about this, we really have to define what we mean by usage. All the neurons in the brain are spontaneously firing all the time, so by that means, given a sufficient time window, we're using all of our brain all the time. Would you define usage as activity above a certain threshold in a certain neuronal population? We could do that, but then you would have to specify a specific amount before saying anything about any percentages of the brain being in use at any given time point.
  14. Could you please provide a source supporting this claim?
  15. Then I have a question. What's the difference between EEG and EMG? Both just measures electrical activity, right?
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