How does complex behavior spontaneously emerge in the brain? http://phys.org/news/2013-08-complex-behavior-spontaneously-emerge-brain.html Quoting from article: In a new study published in Nature Physics, a team of researchers from Spain has shown that emergence in neuronal networks can be explained as a noise-driven phenomenon that is controlled by the interplay between network topology and intrinsic neuronal dynamics. In this scenario, a randomly fired pulse propagates through the network and is amplified by noise focusing, which the researchers describe as an implosive concentration of spontaneous activity. "From the experimental point of view, we show that in neuronal cultures, the emergence early in the development of collective spontaneous activity is dominated by the presence of activity waves that initiate in specific regions of the culture, in a similar way as it happens in vivo," lead author Javier G. Orlandi at the University of Barcelona told Phys.org. "And with the help of simulations, we also show that you don't need any special mechanism to explain this behavior, just the right combination of network structure and dynamics. These waves emerge naturally from the noise focusing effect, in which individual firings propagate and concentrate in specific regions to later generate these activity waves."
... [and a few paragraphs later] "The view ofemergence in neural networks as a noise-driven phenomenon differs from the common view in which the bursts of neuronal pulses are controlled by specific leader neurons assisted by the network architecture. In the noise-driven explanation,the nucleation sites do not actively initiate the firing process, but collect and amplify the firing activity that originated elsewhere. An example of how outcomes in highly parallel systems are often driven by indirect causality. The brain does not just work based on simple cause and effect, there is no clear deterministic path that a thought will follow as it moves from some triggering sensorial event or memory through all the steps in its proto-inception in our pre-conscious minds and finally -- if we ever become aware of it -- into the locus of our focused attention. How these transient synchronized neural firing networks grow and also subside -- and based on what feedbacks they gain or lose momentum is of great interest to me and seems quite critical -- IMO -- to understanding the algorithms of awareness and conscious intelligence. From what I have read the synchronization of firing is one of the key ways in which signal is disambiguated from noise by the brain. I have also heard that these highly transient dynamic phenomena are very numerous and that there are many such firing networks operating at any given instant of time. Essentially the algorithm uses the temporal synchronization that is somehow settled upon by the firing network -- not clear to me how a firing consensus is arrived at -- and that kind of like a Christmas tree where say all the red lights flash -- nearly at the same time -- then the green ones and so on. the network (defined as color in this case) really visually pops out at you - versus trying to put it together if random lights were firing off without being synchronized on some time pulse. It is an effective and economical algorithm too. This may be an indication of how the dynamic transient synchronized firing network emerge in the first instance, if further study bears the findings out in an actual living brain as opposed to a neural culture. Consensus building algorithms also seem to play a vital role brain functioning and I have seen studies that indicate the widely distributed consensus networks of neurons -- as opposed to being highly clustered within specialized brain regions -- seem to be critical in decision making by the brain. Decisions seem to be arrived at by consensus building networks of enlisted neurons -- that may have other primary functions, but that also seem to be doing double duty by becoming enlisted in these transient networks. Who knows at this point how it really all works out, but with each new breakthrough and experimental insight we achieve we are beginning to get a first picture. I, for one am fascinated to see how it unfolds and to perhaps, be among the first generation of people who know how our brains work -- as opposed to arguing about how they work from a position of ignorance. -Chris -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
