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Mapping the Brain's Neural Network
Ponca City, We Love You writes "New technologies could soon allow scientists to generate a complete wiring diagram of a piece of brain. With an estimated 100 billion neurons and 100 trillion synapses in the human brain, creating an all-encompassing map of even a small chunk is a daunting task. Only one organism's complete wiring diagram now exists: that of the microscopic worm C. elegans, which contains a mere 302 neurons. The C. elegans mapping effort took more than a decade to complete. Research teams at MIT and at Heidelberg in Germany are experimenting with different approaches to speed up the process of mapping neural connections. The Germans start with a small block of brain tissue and bounce electrons off the top of the block to generate a cross-sectional picture of the nerve fibers. They then take a very thin slice, 30 nanometers, off the top of the block. 'Repeat this [process] thousands of times, and you can make your way through maybe the whole fly brain,' says the lead researcher. They are training an artificial neural network to emulate the human process of tracing neural connections to speed the process about 100- to 1000-fold. They estimate that they need a further factor of a million to analyze useful chunks of the human brain in reasonable times."
Not to mention - and I a sure I'll get modded down here - is that neural networks aren't very effective. They get a lot of hype in the media, and people who don't work in optimization like them. They sound appealing and cool, but there are other methods that are much better. If you look at the liturature, there is not that much hard science behind them. Some statistical mechanics people have some results, but they really are just a fad, like fractals or catastrophe theory. But bear in mind LOTS of people in applied areas immediately jump to the conclusion that neural networks are great, especially computer vision and robotics people (where I used to work.)
Many engineers have studies feed-forward neural networks and found them to be far inferior to other solutions. Of course, our brains use recurrent neural networks, which, unfortunately for engineers, are very difficult to analyze. There are many secrets yet to be teased out of these neural networks, but much progress has already been made. Researchers in our lab, for example, have demonstrated how introducing random synaptic failures improves not only energy efficiencies, but also the cognitive abilities of simulated neural networks. I'm currently researching the effects of variable activity (as measured in a biological neural network by an EEG), and I dare say there's a lot more that we don't know about these networks than we do.
Ben Hocking
Need a professional organizer?
Hell, it will be fun to see what they figure out to be the capacity of the brain, as far as how much information it can store.
I know visually we are looking at least at something around 24 frames per second. The eye is supposed to have a resolution of around 1000 dpi. Not sure how to measure the viewing area. But let's say it is lesser and lesser resolution the higher the angle. Let's say, just to have a number, that we have a 16:9 viewing ratio at two feet distance. Lets say it's three feet wide. That should add up to something around 36"x20". At 1000dpi that would be something like 729,000 dots. Time 24 per second becomes 17,496,000 dots per second.
Though I think people who have dissected eyes and the stem to the brain would have a hard time quite understanding how that dpi reaches the brain.
On a daily basis, if we don't count 8 hours sleeping, we still come up with 280 million pieces of data in 16 hours.
If an average brain is 1400 cubic centimeters or 85 cubic inches, how many cells could it have if we say it is solid. Best case scenario.
I see numbers of 9,350 cells per cubed millimeter which is 93,500 per cube centimeter. With the above brain size we are looking at 130,900,000 cells in a solid brain.
To complicate things further, how many days of memory do you have? Most people have problems remembering all details but then some people have photographic memory. Which as far as I can see means that all of us has the potential to have it.
The running question is how much info is stored in each cell.
Of course that's not including all the other senses and impressions that are stored.
and it's only like 302 neurons,so,it's possible to write a simulator of it?