Steve, I'm not sure that you recorded action potentials (APs) . Do you have a clear image of recorded spikes. Dorian
On Fri, Jun 29, 2012 at 4:34 PM, Steve Richfield <[email protected]>wrote: > Dorian, > > Look again at those graphs. Action potentials come and go in > sub-millisecond times, yet those "spikes" are tens of milliseconds long. > Either there is something wrong with the apparatus (I always used coaxial > "driven shields" to eliminate the effects of capacitance, etc), or there > are LOTS of neurons involved in making those slow "spikes". > > On Fri, Jun 29, 2012 at 3:53 PM, Dorian Aur <[email protected]> wrote: > >> The signal from every "antenna" can be used to see what happens inside >> the cell during action potential generation (1ms) in vivo, see the papers, >> http://neuroelectrodynamics.blogspot.com/p/spike-directivity.html > > > Note that most people expect 1/r^2 dropoff with distance, but with long > neurons, the dropoff is only 1/r. Worse yet, if you haven't well grounded > things so that dropoff can happen (and the "floating" nature of the curve > literally screams of bad grounding), there is NO dropoff at all with > distance - you see everything there is to see, all superimposed, like in an > EEG. Indeed, note the similarity in appearance with an EEG. > > >> With single electrodes in vitro,the phenomenon cannot be observed >> > > Thereby proving that it doesn't exist. > > Anyway, our discussion here illustrates the sorts of disagreements that so > often exist when neuroscience meets computer science. It takes scrupulous > attention to details to be able to capture things you can really believe, > and there are SO many subtle indications of things that aren't really > happening. > > Speculation on inadequate evidence is GOOD, because without it the field > could not advance. However, be careful not to become too invested in your > speculations. To illustrate, I first "proved" that at least some neurons > communicate the logarithms of probabilities of assertions being true, only > to decades later show that more likely those same neurons are communicating > the derivatives of the logarithms of probabilities being true. > > In this business there is very little that can be proved, only disproved, > and then only under certain particular circumstances. > > Steve > ================ > >> On Fri, Jun 29, 2012 at 2:39 PM, Steve Richfield < >> [email protected]> wrote: >> >>> Dorian, >>> >>> On Fri, Jun 29, 2012 at 2:05 PM, Dorian Aur <[email protected]> wrote: >>> >>>> Excellent topic. During every action potential every neuron *solves* an >>>> n-body problem analog ‘doing’/ execution and the information is >>>> electrically carried and integrated in the brain >>>> http://neuroelectrodynamics.blogspot.com/p/spike-directivity.html *The >>>> fundamental process of computation by physical interaction in the brain has >>>> been widely misunderstood*. >>>> >>> >>> I think the thesis of this site is misdirected. extracellular recording >>> involves using a sort of "antenna" that collects not only the cell you are >>> near, but also other nearby cells all added together. Hence, OF COURSE you >>> will see apparent modulation, even when it isn't actually there. >>> >>> There has been most of a century of intracellular recording, where they >>> impale a neuron with an electrode and look at what is happening inside the >>> cell. Those experiments have observed NO such modulation. >>> >>> It appears that the value being transmitted is a function of the >>> separation between spikes. This is NOT linear, and closely placed spikes >>> count as MUCH more than isolated spikes. >>> >>> However, information travels BOTH ways on axons, and there may even be >>> more than one "forward channel" as ions travel both ways along axons. >>> >>> However, only a tiny percentage of neurons, mostly ones with really long >>> axons (often long enough to see even without a microscope) to transmit >>> their information to a distant place, even produce spikes. The vast >>> majority of neurons simply vary their potential as they "compute", all >>> without producing any spikes. >>> >>> Steve >>> >>> *AGI* | Archives <https://www.listbox.com/member/archive/303/=now> >>> <https://www.listbox.com/member/archive/rss/303/17795807-366cfa2a> | >>> Modify <https://www.listbox.com/member/?&;> Your Subscription >>> <http://www.listbox.com> >>> >> >> *AGI* | Archives <https://www.listbox.com/member/archive/303/=now> >> <https://www.listbox.com/member/archive/rss/303/10443978-6f4c28ac> | >> Modify <https://www.listbox.com/member/?&;> Your Subscription >> <http://www.listbox.com> >> > > > > -- > Full employment can be had with the stoke of a pen. Simply institute a six > hour workday. 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