Shrimp have the world record for impulse conduction speed

[Mk]

I read on Wikipedia:

At 200 meters per second, the myelinated giant interneurons of pelagic penaeid shrimp have the world record for impulse conduction speed in any animal, including vertebrates.

Is myelinated interneurons redundant? If not, why?

What's being done about getting this stuff into human brains? How is this myelin different?

- Wah! mk.

 

[somasimple]

Hi,

80% of our brain neurons are meylinated! I prefer my slow brain than a shrimp one. This speed isn't necessary for us and BTW some of our neurons work at 150/180 meters/s.

 

[Mk]

Yes, but the shrimp brain's myelin is much better than the human brains right? Its faster, and I would like it if I could think faster, have faster reactions and possibly learn better?

 

[somasimple]

Nature chooses a middle strategy:
The most is ennemy of the good.

You are speaking of interneurons and shrimps. It works for this species but won't for man since some neurons have a length of 1 meter. The synchrony will be lost if you enhence the speed.

 

[DocToxyn]

There are a few things to consider here. It's not just the myelin that contributes to the shrimps high conductance speed. Conductance along an axon is a dynamic process of opening and closing of ion channels, exchange of ions and numerous other processes. The myelin serves as an insulator which allows for more efficient travel of the electron flow. So it may not be that the shrimp myelin is better, but that the system as a whole is better. Also "better" may not be the best word to use, better in terms of what it needs to do, but pehaps limited by such speed for some other application.


The other issue is that this is most likely not an issue of "thinking" or processing speed, but more of a reaction-type response. Perhaps this shrimp require extremely fast responses to the environment in order to avoid predation. It doesn't mean that this shrimp can "think" faster than us, a lot of nerve conduction has nothing to do with thinking, eg. muscle contraction. Ability to think or mind power or whatever you want to call and it's relationship to learning and the human condition cannot be simply boiled down to how fast does a specific nerve conducts a signal. It's a complex interplay of neurons and nuclei and communication that seems plenty fast enough for me.

 

[somasimple]

The myelin serves as an insulator which allows for more efficient travel of the electron flow.

The myelin is effectively an insulator but why is there 200 or more wraps? One would be sufficient!

It is not an electron flow, IMHO, since you said it uses ions that cross/travel the membrane. (But it is the traditional theory).

 

[kublai]

Sort of an aside to the main topic, myelin serves several purposes besides insulation. It structurally protects, it is a conduit of neutrients and waste, it serves to bundle the nerves for organized routing, allows bending without kinks, allows stretching and some more that I can't think of right now.

 

[somasimple]

Fine response!