Medical Brain Influences Itself with Its Own Electric Field

[rhody]

Ok, thread bump turns into thread crash...

I saved this link awhile ago article was posted in April 09, I was digging through my links and thought it may be worth posting. Maybe not, considering this tough crowd.

http://www.wired.com/wiredscience/2009/04/Newtonai/"

The researchers have already applied the program to recordings of individuals’ physiological states and their levels of metabolites, the cellular proteins that collectively run our bodies but remain, molecule by molecule, largely uncharacterized — a perfect example of data lacking a theory.

Their results are still unpublished, but "we’ve found some interesting laws already, some laws that are not known," said Lipson. "What we’re working on now is the next step — ways in which we can try to explain these equations, correlate them with existing knowledge, try to break these things down into components for which we have clues."

Lipson likened the quest to a "detective story" — a hint of the changing role of researchers in hybridized computer-human science. Programs produce sets of equations — describing the role of rainfall on a desert plateau, or air pollution in triggering asthma, or multitasking on cognitive function. Researchers test the equations, determine whether they’re still incomplete or based on flawed data, use them to identify new questions, and apply them to messy reality.

Redemption ? or more cone of silence and near thread death ? lol.

Rhody...

 

[Pythagorean]

For "strange attractor" chaos, the largest lyapunov exponent is negative when you are "on" the attractor. In transient and stable chaos the lyapunov exponent is negative "on" the attractor, but the transient behavior appears very complicated. Transient and stable chaos are distinguished by positive and negative lyapunov exponents on the transients.

http://arxiv.org/abs/cond-mat/0401038
http://arxiv.org/abs/cond-mat/0603154
http://www.frontiersin.org/Computational_Neuroscience/10.3389/neuro.10.013.2009/abstract

thank you atyy, I didn't notice this post last time.

 

[Q_Goest]

Hey Rody, I enjoyed your links. Thanks.

atyy, congrats on being awarded SA.

 

[Pythagorean]

Thanks for the responces, folks. Perhaps I should clarify the question. My understanding is that neurons fire because of what occurs at the synapses (ie: they exchange information or interact at the synapses) but my impression is this article is suggesting neurons are interacting through this electric field as well. To what extent is this paper saying they intereact? Is it only that they synchronize their firing or is the author suggesting neurons are also 'talking' to each other through this field? That is, are the neurons allegedly exchanging information through the field in the same way they exchange information through synapses?

Theoretically, if you apply an electric field to a neuron, you could bring it closer to (or further from) threshold.

So if you have a whole network of neurons and you entrain them all with the same field, you're simply bringing them all closer to threhold at once, increasing the chance anyone of them will fire.

Whether the the brains electric field can actually do this, I'm not sure. Technically, there's induction between electrcally active neurons. But is it significant enough to affect the membrane potential? I think we'd néed more research results.

 

[minorwork]

Theoretically, if you apply an electric field to a neuron, you could bring it closer to (or further from) threshold.

So if you have a whole network of neurons and you entrain them all with the same field, you're simply bringing them all closer to threshold at once, increasing the chance anyone of them will fire.

Whether the the brains electric field can actually do this, I'm not sure. Technically, there's induction between electrically active neurons. But is it significant enough to affect the membrane potential? I think we'd need more research results.

Is taking a neuron for being the same type of conductor as a copper wire a bit of a stretch? Inductance's effect on current from a changing magnetic field is out of phase with a changing electric field's effect on current in a circuit.

 

[Pythagorean]

Any moving charge generates fields; Especially in the myelinated case, where the majority of ions travel quickly down the axon between the nodes. Are they significant fields? I don't know.

 

[apeiron]

Any moving charge generates fields; Especially in the myelinated case, where the majority of ions travel quickly down the axon between the nodes. Are they significant fields? I don't know.

Myelinated axons produce little in the way of local field potentials because they are, well, insulated.

If endogenous field effects are computationally important, then it is the dendritic synapses, and probably the axon hillock even more so, which would likely be the generator.

This is why it is plausible that hippocampal pyramidal cells might use this mechanism (they are like little oriented dipoles with a bunch of dendrites one end, a fat axon at the other). But stellate cells wouldn't (dendrites all over the place that cancel each other out).

 

[Pythagorean]

Myelinated axons produce little in the way of local field potentials because they are, well, insulated.

If endogenous field effects are computationally important, then it is the dendritic synapses, and probably the axon hillock even more so, which would likely be the generator.

This is why it is plausible that hippocampal pyramidal cells might use this mechanism (they are like little oriented dipoles with a bunch of dendrites one end, a fat axon at the other). But stellate cells wouldn't (dendrites all over the place that cancel each other out).

Just being insulated isn't enough of course until you've done the calculation to compare the higher current to the higher reluctance. And apparently, somebody has already bothered with the crayfish:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1327234/

(their result was as you say, negligible)

But I'm curious whether the electric fields are coupled through magnetic fields or concentration gradients or both?

 

[giann_tee]

The article sounds implausible to me, because neurons in the brain are extremely interconnected. Any destination neuron is reachable in 3 steps, so the strong interneuronal couplings must be the primary interactions that determine how the whole network will behave. On the other hand, I recall the elementary electric oscillating circuit, comprised of two elements, the capacitor and the solenoid. When the capacitor releases its current, the current builds the magnetic field. When the magnetic field in the solenoid degrades, it induces a reverse current that refills the capacitor. A neuron is a charged capacitor and a battery. Where is the influence of the transient magnetic field then? It is probably somewhere there, but it is very small.