The name is absent

78

we deconvolve the networked rod response with the theoretical isolated rod response to
yield a unit-less response profile that represents the contribution of coupling on the rod
response (figure 5.2D). Deconvolving the networked response with the theoretical isolated
rod response eliminates both the nonlinearity present in the rod light response sensitivity, as
shown in figure 5.2 B, and the contribution of light scattering that would otherwise confound
our analysis.

As expected, the resulting response profile is narrower than the actual rod response. By
fitting single exponential decay of the form of 5.4 to the ideal network response, we calculate
the space constant on each side of the ideal response profile, yielding values of Лщ - 17.4
(Pearson’s R=0.955) and 9.8 μm (R=0.997), as shown in figure 5.3 B and C.

Assuming a cell spacing D = 16 μ [8], λιr>∕D = 1.09,0.61. Using the relation for a 1-
dimensional network, equation 5.5, the ratio 7 = R_c∕R_m of coupling resistance to membrane
resistance was calculated, which corresponds to values of 7 = 0.91 and 3.31, for the 17.4 and
9.8 μm measurements respectively [69]. Assuming an isolated rod membrane impedance
R_m = 300 MΩ, these values of gamma would correspond coupling resistances R_c of272 and
994 MΩ. Table 5.1 outlines these values.

5.3 Measurement of coupling resistance using electrical stimuli

Whole cell patch recordings of adjacent rods were made in the whole retina in order to mea-
sure the coupling resistance between rods in the network. Voltage clamp steps from -120 to
+20 mV applied to one cell caused currents in an adjacent cell which was clamped at -40

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