Autism as an electrical disorder.

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It might help to understand what the paper is discussing.

When the neurons are formed that go to the neocortex, they are not formed in place. Rather, they are formed and then migrate to their eventual place along tiny glial fibers. There are generally six layers of neurons in the neocortex with the first layer on the inside and the sixth layer on the outside. As the neurons are formed, they migrate into position building the brain from the inside out. That is, the first neurons go to first layer with later neurons going to the second, the third, and so on until all six layers are built. This entire process in humans is in, I think, the middle trimester of gestation. Only once they are in place are the neurons differentiated -- that is, become the type of neuron that they will be.

I only know of one mammal that is born with the brain still being developed. That is the ferret. If I remember correctly, the development of the brain in the ferret continues for something like two weeks after its birth.

So when the article says "Migration of neurons to achieve their final locations follows on the heels of proliferation. Differentiation includes maturation of electrical excitability, transmitter specification, and outgrowth of axons and dendrites." that is what the author is talking about.

Note that as far as the neuronal proliferation, he is talking about electrical signaling by the release of various neurotransmitters by the cells that are dividing to produce embryonic neuron cells. That is, the neuroblasts can respond to the general activity of other neuroblasts and either increase or decrease their rate of production as need be.

Apparently the same type of activity can guide the neurons to their proper place as they migrate to their final position. (I've wondered how they knew when to stop.) The sentence "Radial migration of postnatal mouse cerebellar granule cells along Bergmann glia depends on activation of voltage-gated N-type Ca channels and the NMDA (N-methyl-D-aspartate) class of glutamate receptors, which generate fluctuations in intracellular Ca ions that are positively correlated with their rate of migration." That is, if the amount of Ca ions is high, the neuron knows that there are other neurons around it and it keeps moving. As the concentration of Ca ions is lowered, the neuron slows down and when the concentration of Ca ions is low enough, it stops in place.

As for the neuronal differentiation, at that point there is going to be plenty of local activity between the neurons. There isn't going to be any large scale flow of action potentials at that stage.

None of this involves any general electrical activity of the brain. Once the brain is developed and capable of general activity, it is pretty much through adding neurons. There is some capability to grow more neurons, but I think that it is pretty limited.

I should note that is quite an interesting paper. I took a graduate Neuroscience course years ago and we discussed how the neurons are created and then migrate into position before differentiating into various cells, but we never discussed the signaling mechanisms themselves.

Can we take this back a few steps:
This idea makes no sense, but it could spur you to learn more about how the nervous system works, then it's good. Go read the wikipedia page on neurons. And Electricity.

I believe that many mental disorders/disabilities are a result of misfiring synapses.

Like as a result of water intoxication?

We really have no way of knowing at this point in time if hyperactivity of a brain region is the result of overactive electrical impulses or the release of too much excitatory neurotransmitter causing too many electrical impulses. And remember- it could also be that the INHIBITORY systems are not working enough, allowing for the system to go haywire.

Thank you for typing all that out, admittedly I don't follow it entirely, but I understand current contexts of science may not point towards such a thing.

But despite that, and I ask you this because you appear to have read more about it. Leaving aside limitations of current theories. You really believe there is no possible link at all, in anyway, that increased brain activity could result in more brain mass? It is entirely conclusively been proven as false in any possible way? Potential brain mass is absolutely dependent on non-electrical factors decided at initial formation?

I think it's probably the opposite- a lack of "pruning" brings about the result of overactivity, due to too much gray matter. I'm a big proponent of this hypothesis for the neuropathology of OCD.