Lee Kent Hempfling (lkh at mail.cei.net) wrote:
>> It is a very common misconception that neurons only fire.
Assuming that you mean firing as an action potential, that is what they
commonly do as an output.
> What neurons
> do is accept a charge value, hold it until they accept a second charge
> and the result of the calculation is discharged from the neuron. It is
> this discharge that is observed as firing.
Nope. They accept many inputs. If the temporal and spatial summation of
inputs leads to a threshhold level, they will fire an AP. After that,
they are refractory for an interval. It is the refractory period
that limits the 'firing' frequency.
> There is no noise in that
> process. If there was, we would all be dealing with incorrect sensory
> perception.
Sure there is: spontaneous transmitter release at the synapse. Of
course, such events are unlikely to significantly influence the next
neuron's firing.
> It is not a binary function. >
Depends on your definition. After all, it either fires an AP or it
doesn't.
Kal