Blog Directory : Listing Details
Brain Stimulant details
Listing ID: 45
Title: Brain Stimulant
Description: Covering several topics about the brain, neuroscience, neurotechnology and artificial intelligence.
Category: Science
Owner:
listed on: March 30, 2008 11:28:23 PM
Number Hits: 0 times
Recent Posts:
| Neuromorphic Brain Emulation - Thu, 20 Nov 2008 18:26:33 -0600 |
 The US government's Defense Advanced Research Projects Agency (DARPA) has given a 4.9 million dollar grant to I.B.M. research and five universities for a new project. They basically want to reverse engineer the brain on a neuromorphic chip. I have mentioned about DARPA doing thisin the past. However, then the deal was not yet finalized. You can read about the contract atDARPA's website. At the I.B.M. Almaden Research Center, Dharmendra Modha is now currently the manager of cognitive computing. You can read more information about this project atModha's blog. Modha’s team has already been trying to reverse engineer the human brain. Modha estimates that by 2018 we will have the capability to simulate the entire human brain in real time on a computer. Modha’s group has already published a paper about simulating a rat brain in real time.The human cortex has about 22 billion neurons which is roughly a factor of 400 larger than our rat-scale model which has 55 million neurons. We used a BlueGene/L with 92 TF and 8 TB to carry out rat-scale simulations in near real-time [one tenth speed]. So, by naïve extrapolation, one would require at least a machine with a computation capacity of 36.8 PF and a memory capacity of 3.2 PB. Furthermore, assuming that there are 8,000 synapses per neuron, that neurons fire at an average rate of 1 Hz, and that each spike message can be communicated in, say, 66 Bytes. One would need an aggregate communication bandwidth of ~ 2 PBps.Modha also believes that nanotechnology will enable researchers to develop and replicate at the nano-scale the structure of a real human brain. Modha recently gave a talk at the2008 singularity summit. Here's an excerpt from theIBM press releaseabout this new project. IBM and its collaborators have been awarded $4.9 million in funding from the Defense Advanced Research Projects Agency (DARPA) for the first phase of DARPA’s Systems of Neuromorphic Adaptive Plastic Scalable Electronics (SyNAPSE) initiative. IBM’s proposal, “Cognitive Computing via Synaptronics and Supercomputing (C2S2),” outlines groundbreaking research over the next nine months in areas including synaptronics, material science, neuromorphic circuitry, supercomputing simulations and virtual environments. Initial research will focus on demonstrating nanoscale, low power synapse-like devices and on uncovering the functional microcircuits of the brain. The long-term mission of C2S2 is to demonstrate low-power, compact cognitive computers that approach mammalian-scale intelligence.Its still too early to say how much this research will actually accomplish. I suspect we may be able to simulate some of the processes of the brain relatively well. However, I think it may be fairly difficult to get that brain to be conscious. If we do successfully replicate consciousness it brings up all sorts of ethical issues, like how ethical is it to make a conscious human brain replica? There are a variety of ways of going about creating a brain. This could include computer brain simulations (seehereandhere),neuromorphic chipsor even possibly using stem cells tosynthesize whole brain tissue. I think eventually we will be able to replicate a brain fairly well. If not on a computer or neuromorphic chip, then definitely using actual neurons possibly created from stem cells. Sufficiently advanced nanotechnology should allow the precise placement of neurons, dendrites and synapses. With sophisticated brain imaging techniques, this could allow scientists to create an exact replica of someone's brain. |
| RNA Interference for Parkinson's Disease - Wed, 19 Nov 2008 09:09:47 -0600 |
 Parkinson's diseaseis a fairly devastating illness.Dopaminergicbrain cells die off over the course of this brain disorder. As brain dopamine levels fall, patients often have increasing difficult moving. They may show signs of tremor, muscle rigidity, a slowing of physical movement and sometimes a complete loss of physical movement. Patients become increasingly trapped in a body that ceases to function normally. There are a variety of drugs that are used to artificially increase the neurotransmitter dopamine in the brain. These drugs include dopamine agonists, dopamine precursors and drugs that inhibit the breakdown or reuptake of dopamine. In the future, successful treatment of parkinson's disease will need to be able to slow down the death of dopaminergic brain cells that synthesize dopamine and not just replace the missing dopamine. Doing this would allow a patient to retain their functioning without a large decline.Now researchers at theMayo Clinicare testingRNA interferenceto reduce the alpha-synuclein protein in the brain. Too much of the alpha-synuclein protein can accumulate in certain parkinson's patients and this is believed to be the cause of some of the brain cell death in these people. RNA interference is a way of selectively knocking down the functioning of a specificgene. It can selectively reduce the amount ofproteinbeing synthesized by that gene by introducing a short RNA strand. In a recent study, scientists infused small interfering RNA's into the brains of mice. They found that the RNA Interference was able to silence the alpha-synuclein gene and reduce the production of the alpha-synuclein protein for approximately 3 weeks. There are quite a few problems with RNA interference. Problems include making sure that the RNA interference knocks down the correct gene and doesn't target any other genes. Also it is difficult to find a proper delivery mechanism for the RNA interference. RNA strands can easily be degraded in the body. Scientists have really been working hard at getting RNA interference to work for many disorders. However, it is currently not clear if they will be able to overcome these hurdles to get RNA interference to be used in real patients. Researchers have recently createdoral pillsthat can deliver RNA interference. So RNA interference may eventually be used for certain brain disorders where knock down of a specific protein is necessary. Here's a video about this new paper. |
| Whole Brain Emulation Roadmap - Mon, 17 Nov 2008 18:55:12 -0600 |
 The Future of Humanity Institutehas just recently published a roadmap that describes what scientific research is required to do whole brain simulation on a computer. Here's a small quote from that paper.Whole brain emulation, often informally called “uploading” or “downloading”, has been the subject of much science fiction and also some preliminary studies (see appendix D for history and previous work). The basic idea is to take a particular brain, scan its structure in detail, and construct a software model of it that is so faithful to the original that, when run on appropriate hardware, it will behave in essentially the same way as the original brain.The 130 page document was created byNick BostromandAnders Sandberg. You can download it here for free (Whole Brain Emulation RoadmapPDF). It looks fairly interesting, but is a little technical. The paper discusesmind uploading. Mind uploading is the science fiction idea of uploading a person's consciousness into a computer via a whole brain computer simulation. In the science fiction novel City and the Stars (1956) Arthur C. Clarke described a far future city where bodies are manufactured by the central computer, minds stored in its databanks downloaded into them, and when an inhabitant dies their mind is stored yet again in the computer, allowing countless reincarnations. Other early science fiction treatments were Roger Zelanzky’s Lord of Light (1968), Bertil Mårtensson’s Detta är verkligheten (1968) and Rudy Rucker’s Software (1979). Since then, mind emulation (“uploading”) has become a staple of much science fiction23.The idea of mind uploading is a little improbable currently, but the paper looks fairly grounded in actual science. |