The name is absent

IOl

Although the steady-state voltage distribution for a continuous network is given by a Bessel
function (equation 5.7), the voltage falloff is well approximated by an exponential decay, as
shown in figure 5.5 D. Therefore, K, the voltage difference between neighboring cells due to
a point source of current can be given by a unit of single exponential decay.

From the definition for hyperbolic sine:

(5.20)

5.6 Coupling and noise in the rod network

Estimates of R_m and R_c are particularly interesting because they describe how rod-rod cou-
pling affects visual signals in the retina. With these estimates from derivations and exper-
iments described in the previous sections, we show that compared to an uncoupled rod
network, rod-rod coupling increases the signal-to-noise ratio of visual information when
image features cover multiple photoreceptors, but reduces it when the input signal contrast
varies from rod to rod.

We analyzed this phenomenon quantitatively using Fourier analysis. Although the steady-
state impulse response contains all of the information about how signals may spread in the

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