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ashennell

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Everything posted by ashennell

  1. To have your own theories about how things work is admirable, even if they unlikely to be accepted by most scientists. Any opinion is better than no opinion. But to use your own ideas as the basis for teaching other poeple how the brain works is wrong. Plain and simple. Your theory seems to stem from some misunderstandings of the basic properties of neurons and is extended and extrapolated using your own 'common sense' reasoning and the word 'ego'.
  2. Your posts are the literary equivalent of footstamping, screaming and bawling. Grow up for gods sake! You sound like a kid who has just realised that the world is not a wonderful perfect place - and now you want someone to blame. Even if there was a shred to truth to what you are saying, do you really expect that your insulting posts are going to achieve anything. The vast majority of academia work very hard for very little money. You seem to think that finding the brightest and best is essential but don't credit these people with enough intelligence to choose themselves how to persue their research. We all know the world is faced with numerous problems. You seem to assume that science should always be able to solve them. It's like smoking 20-a-day, drinking beer and eating fast food everyday for forty years and expecting modern medicine to sort out all of your problems. When the doctors tell you there is nothing that can be done you would probably say -'well there should be, your just not trying. Medicine has failed me.'
  3. This seems to assume that it's the role of science is to save humanity. This seems a bit hypocritical. Why should you be bothered about discoveries of this kind - neither of them have any great significance in sciences role of 'saving humanity.' there are already replacements for many of the uses of fossil fuels. The reason they are not popular is because of money - businesses and governments. WE don't need science to stop global warming we just need to change they way we live. If it wasn't for science we wouldn't even know about global warming. I heard this bull many times.
  4. Well the conclusion I would draw from these three experiments is that dogs have far greater psychic powers than humans. Their task seems far harder than the other two.
  5. Heres an idea sunspot... You obviously have a lot of mental energy that needs to be directed somewhere. So choose a topic, a broad topic, in some area that you are interested. Something like philosophy of the mind or memory and write a review of the that topic. Include nothing of your own work or ideas, just what other people have written. If you feel necessary you could provide a critical analysis of why their work is insuffcient but don't add any extra explanation of your own. Why? - If your review is based on current scientific knowledge then at least other people will be in a position to evaluate your review if it. - If you can do this and have the result understood by others then you can be assured that you are at least thinking rationally and have a sense that your own ideas could be underatood if you expressed the correctly, maybe it would help you express them. - It would give you an in depth understanding of the field that you chose to review and perhaps some new insights. I dont say this to be nasty but given that most people seem to find your posts incomprehensible it could be a good focus for you. If you can't summarise a topic then why would we expect you to provide a new interpretation of it.
  6. I think your way of looking at this makes a lot more sense. I kinda felt my argument here was poor when I was typing it. However, I'm not sure that the amount of precortical processing is important. We both agree that illusions require interaction between top-down and bottom-up info. While passing through the thalamus provides one extra point where this interaction may occur I assume that you would agree that most visual illusions result from computations at levels higher than the LGN, somewhere in the cortex. If olfactory illusions to exist then they would most probably result from processing in the olfactory cortex. I agree that this issue is contentious. I only (edit)accept this as an illusion because of its similarity to the mirage example. I think there are two ways of reasoning about this situation. One way would be as you have outlined above. Another way would be to say the the chemical in question is the smell of both rotting meat and of Amorphophallus titanum, i.e. associating the smell with the chemical and not the causes. There is no basis for the olfactory system to determine which is the correct cause , the assumption of one over another is a mistake at some level. Although this assuption is a valid (and useful) one in most cases. The beetles that head towards Amorphophallus titanum in expectation of rotten meat probably feel tricked. Perhaps I should find an example of two completely unrelated compounds that have exactly the same smell. Would this be acceptible as an olfactory illusion? there are indeed lots of types of illusion. One type that you mention are based on ambiguity - where there are 2 or more valid interpretations of a stimulus. Perhaps there are compounds that smell differently in different contexts. Rather than debating what constitutes an illusion and what properties of a perceptual system are required for an illusion I will try and find an example that we both agree is an olfactory illusion. I will start here: from this site Now don't laugh. I also can't belive that I have been reduced to drawing quotes from a summary of a Perfumer & Flavorist artical. Hey, it's the first thing I found. I would get the whole article but I'm guessing my Uni dosn't stock Perfumer & Flavorist. I'll do a more in depth search later.
  7. Sorry, you didn't say they were impossible - just that they don't exist. Anyway, I'm not here just to start an arguement. I'm not entirely sure myself if olfactory illusions exist but I think it's worth debating. I think I was mainly annoyed because I had alrady replied your orignial post in a more dignified manner, in this post, but it didn't seem to merit any response. I will try and tackle your two main points again briefky- I think that hallicinaitons require interaction between top-down and bottom-up processes moreso than illusions. Yet you have already provided an example of an olfactory hallucination. So why not an olfactory illusion? I agree that this property of the olfactory system allows less scope for both illusions and hallucinations though. Our sense of touch arguably allows even less room for confusion than our olfactory system. All that is required is a mapping from levels of pressure, vibration and muscular feedback. This is compared with the olfactory systems task of representing the presense of almost any molecule. But there are haptic illusions. One of my favourites is the 'Cutaneous rabbit' experiment. This is a tough question. At the moment I would say yes, because I can't find a way to define an illlusion that captures all illusions that we would easily except from those that don't seem right. For example, a mirage is a visual illusion caused by the refraction of light as it enters a layer of warm air near the ground. The illusion is actually an image of the sky or other distant objects being refracted back. This looks like water because water does exactly the same thing. So we could say that our visual system is not being tricked but providing an accurate description of the visual scene. It is our interpretation of the result that it faulty - our assuption that this effect is only produced by water. Is this not the same as assuming that a certain smell is only produced by rotting meat? Edit: bad english
  8. There is no such thing as higher evolution or more highly evolved organisms. Keeping the body at a higher temperature does allow species to be active at lower environmental temperatures but this comes at a cost in terms of energy useage. Intelligence in general (in an abstract sense) is clearly not related to body temperature (my original reply was trying to make this point humerously) but intelligence in animals may be. Big brains use a lot of energy. If our body temperature drops, so does our metabolic rate, a big brain may not receive enough energy to be useful. Animals that live with a constant low metabolic rate probably couldn't support a large brain. For animals whose body temperature varies depending on external heat sources the situation is hard to predict - it would be some trade off between energy cost and benefits from bigger brain that is sometimes active and that could be damaged during low periods of low energy. However, for species that maintain the body temperature at a high level - and have found a good niche that allows them to maintain the high energy demand then the energy consumption issue is probably less important.
  9. Hi, I have been here for a while now and have often wondered why the forums for Neurosience , Psychology, Genetics and Anatomy and Physiology are grouped under the Medicine forum. I can understand that Psychiatry should be somehow linked to medicine. the others are primarily studied out of the context of a pathological state. Would they not be better placed under biology (I'm not sure about the best place for psychology?)
  10. You have been working on this for 15 years? Surely there must have been one moment of clarity in these last 15 years where you sat down and realised that 'this is all nonsense'? Your posts are pretty much undecipherable. You don't seem to appriciate this as your response to requests of clarification have been more posts that are even less clear. This tells me all I need to know about your grand theory.
  11. If warm blood is a prerequisite for intelligence then it would suggest we cannot create an intelligent computer that is cold blooded. So warm blooded computers would be the future then?
  12. this is borderline scientific. He dosn't really make a strong case for this model.
  13. ??? But it's a poor argument!! The description of the olfactory pathways is very interesting, but to assume that olfactory illusions are impossible just because of this seems very naive. There is no law that says that illusions require the thalamus or that primitive senses cannot be fooled. This is just assuption. It is certainly no basis for dismissing the possibility of illusions. Try and find a working definition of 'illusion' that includes all your excepted illusions and that also rules out ethers as olfactory illusions. I think it would be quite difficult. I have also presented some examples of other illusions that are possible borderline olfactory illusions.
  14. You can die from lack of sleep in certain circumstances. Heres a quote from the page I've linked to. Theres lots of otheruseful information in this page as well. http://start.eegspectrum.com/Newsletter/jul2005.htm
  15. Sorry, I cut my list off short As far as I know all animals with complex brains sleep. Sharks probably do sleep, they dont need to stop moving to sleep. As has been mentioned, some dolphins sleep one half their brain at a time. Other dolphin species sleep for 2-3 seconds every couple of minutes (exact details may vary). Some experiments have shown that peformance of a motor task that is being learnt can improve after a period of sleep. this is strong evidence for a link between sleep and learning. I think there is similar evidence from experiments where cognitive tasks are learnt. Finally, during all periods of sleep there is no overall reduction in actually neural firing. Sleep does not reduce the amount of energy used by the brain.
  16. I should think that are millions of people who work nightshift without dropping dead - he may have died but probably notbecauseof his sleeping pattern. I have heard of rare cases where someone cannot sleep at all, not even with anesthetic. In this case, they slowly lose their mental faculties and end up in a coma and eventually die (well, never come out of the coma anyway). Perhaps your own perception of your abilities suggests that they show improvements but a whole hodge of scientific data would suggest otherwise. Have you ever tried testing yourself in certain ways during your prolonged periods of sleep deprevation? yes this is a myth, we use all of our brain. While this is true, the amount of extra sleep required is doesn't depend on the duration of the waking period.If you are awake for 96 hrs you only need to sleep as much as you would if you were awake 2 or 3 days. We know how the onset of sleep is controlled in the brain but I assume you would like to know the function. There is no definate answer yet. I have provided a list of things we are reasonable sure about as well some of the current ideas - the brain needs sleep and not the body. We Feel tired to make us go to sleep and not because our body is literally exhausted. If we overwork our muscles we get cramp. Any benefits the body receives during sleep are secondary to the needs of the brain. Sleep may allow down-regulation of synapses - the strength of which, it is proposed, are generally increased during active behaviour. Sleep may allow consolidation of the memories of experiences from the previous day. time to push things into long term memory. (My idea) The absence of dominating sensory input may allow our internal generative model to reinforce itself. This may make little sense. A generative model is a model that makes predictions of its sensory input. we can use this model to plan a head a little (ahead of real time) but this requires that our predictions don't match current input. Perhaps the lack of sensory input allows some time for these 'planning-ahead' associations to be reinforced with out constant errors in prediction.
  17. I don't think there is a problem with studying homosexuality in a scientific way. Surely you could just apply your attitude to everything in nature and not bother studying anything i.e. - 'The universe is cool we shoud accept it instead of analysing how it came about.'
  18. Can you provide some evidence of it's existence? All I get from googling is your posts in various forums and other unrelated stuff. A 1D hyperlink to a 2D webpage would be suffcient.
  19. If you want to be a neurosurgeon you have to become a MD first. If you want to be a neuroscientist, i.e. a non-clinical researcher, then you should do a suitable degree - biology, biochemistry, psychology. Actually a lot of neuroscientists orginally did a degree in physics. It's quite multidisciplinary field so there are a lot of ways into it. But it sounds like you want to be a neurosurgeon - go to medical school. I'm the UK, not the US but I think it all works pretty much the same over there.
  20. In addition , The maximal firing rate for a neuron is less than 1KHz which means that any soun dwith a frequeny greater than this cannot be encoded by firing frequency. I think the upper limit on human perception of sound is approx. 20000KHz. Also, the lower frequencies, like middle C, would not stick out because these are the kind of frequencies that neuron opperate at.
  21. Frequencies of what? I assume you mean firing rates or frequencies recorded from EEG's rather than actual sound waves. The cochlea (in the inner ear) recodes incoming soundwaves in a way not too dissimilar from applying a fourier transform to the input. this means that input arriving at the brain is essentially spead out across the neural inputs as a mapping based on the frequencies contained in the input signal - a spectrum. One subpopulation would code around 260 Hz and another would code slightly higher, etc., etc. Given this, a single C note would be signalled by activity in a population of neurons, but the activity of these neurons does not need to be at 261.63 Hz, instead the peak (or local average) of activity would be at the neurons that represented this frequency in the spectrum. There could be some extra phase locked activity but I really don't remember. Somebody else may be able to provide a more accurate description of what occurs but I think this is basically correct. The short answer : internal representations of stimuli do not have to have properties of the stimuli that create them.
  22. PC memory is accessed by address and the brain appears to be access its memory by content. There is little similarity between these systems. However' date=' is it fair to say that even in toy neural networks that we have today the 'memories' are stored in very high dimensional space, as weight vectors. The importance of 1D , 2D and 3D doesn't make sense to me. there is no way that a humans whole memory is stored in a 3D space. By the way, what kind of memory are you talking about, working memory, episodic memory, declarative memory, procedural memory, etc., etc.? So one axis is cause and the other is effect? This gives a one to one mapping between causes and effects or do ou allow one-to-many? So how is a logical function represented , e.g. XOR , NOT, AND etc. How can the order of execution be demarked in a logical train of thought that you mention - there seems to be no means of determine which step comes 12t, 2nd. You only need 3 dimensions not many differnt planes to get 3d. This is equivalent to just stacking the planes on top of each other - you gain nothing unless the first two dimensions of each plane have similar meanings.
  23. Conspiracy theories are propagated by people who revel in the idea of knowing more about a particular event or having the inside story even if there extra details are unfounded - it is a conversation piece at best. This particular example is annoying because there are so many real issues that people should be considering. Why is there such a difference in opinion between western values and those of other cultures, etc, etc. This kind of talk just distracts attention from what is really important. Kiddies can constuct their conspiracy theories and be playground prophets if they choose - I would rather discuss the issues that definately face us rather than the ones that might do given a string of spectacular coincidences and secret plots.
  24. a friend of mine has this blog which includes an article about this issue that might be interesting - http://wallsmirrors.blogspot.com/ . I pretty much agree with his point of view. 'Natural' dosnt have a consistant definition so argueing whether something is natural or unnatural is pointless.
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