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Author Topic: What is the current of human nerve impulses?  (Read 4800 times)

Offline ChaosD.Ace

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What is the current of human nerve impulses?
« on: 16/10/2013 14:28:22 »
How many Amps in action potentials down the Spinal Cord?


 

Offline peppercorn

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Re: What is the current of human nerve impulses?
« Reply #1 on: 16/10/2013 14:31:48 »
'action potentials' - ??
Nervous system signals are of the order of micro-amps I suspect.
 

Offline ChaosD.Ace

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Re: What is the current of human nerve impulses?
« Reply #2 on: 16/10/2013 14:37:32 »
Cool, How many micro-amps?
 

Offline dlorde

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Re: What is the current of human nerve impulses?
« Reply #3 on: 16/10/2013 17:50:26 »
There is no overall current down the axon of a nerve cell; it isn't like electricity in a wire, it's more of a chain reaction that moves along, like a burning fuse - but unlike a fuse, it resets itself again ready for the next pulse. The action potential is a wave of depolarization (ions flowing in or out according to charge differential) moving down the nerve membrane, so any voltage change is between the inside and outside of the cell membrane (from about -75mV to a maximum +55mV) as the wave passes. See Action Potential.
« Last Edit: 16/10/2013 17:56:20 by dlorde »
 

Offline evan_au

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Re: What is the current of human nerve impulses?
« Reply #4 on: 18/10/2013 22:10:44 »
The pattern of current flow in the axon is radial, with ions being pumped in & out of the axon as the nerve impulse passes by.

We could calculate the current with the following inputs:
  • Which type of ions? (Na+ & K+ both have charge +1)
  • How many ions pass through an ion channel for 1 nerve impulse?
  • Over what period of time?
  • This calculates the peak current in 1 ion channel
  • (The density of ion channels on an axon) x (area of the axon) gives the total current for 1 nerve impulse in 1 nerve cell. 
  • Multiplying by the number of nerve impulses per second gives the average current. 
 

Offline ChaosD.Ace

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Re: What is the current of human nerve impulses?
« Reply #5 on: 20/10/2013 13:47:01 »
Thanks a lot evan_au that's really helpfull.
 

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Re: What is the current of human nerve impulses?
« Reply #5 on: 20/10/2013 13:47:01 »

 

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