[Comp-neuro] Noise, redundancy and biophysics

[G. Bard Ermentrout]

I want to once again emphasize that the "noise" that we discuss in our 
paper is not meant to be a distraction but rather is the signal in the 
sense that we do not know precisely the nature of the summed EPSPs and 
IPSPs that are felt at the site of AP generation. Thus, we are using a 
broadband input to study how a neuron responds (in some sense, like the 
ideas of many others, notably Bialek, Berger, et al) reliably when it is, 
in absence of input, firing an a fairly regular fashion. This is a 
somewhat restictive environment (admittedly)  and we mean by noise the 
form of the signal - as it is repeatable, it is not noise in the 
engineering sense of something to be avoided. I agree with Sacha (at least 
at the hillock), that channel noise is not an issue. We were interested in 
whether a broadband signal could get through reliably in the presence of 
other signals that are of different origin (and treated as "noise" with 
respect to the first signal).

Bard