The name is absent

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tor. Because cones are not coupled to one another, the recorded response comes only from
that cone. We compensated for the nonlinear response of the cone by using its nonlinear
sensitivity relationship (figure 5.2 B) to find the intensity of the scattered light from the bar ?
as a function of position. We then transformed the profile of the scattered light to predict
the hypothetical uncoupled rod response, and deconvolved the actual measured response
from the rod network with this hypothetical uncoupled response. The resulting predicted
network response gave estimates of ʌɪp = 17.4 and 9.8 μm. The latter estimate gave a far
better fit to the expected exponential decay.

One drawback of this measurement technique is that while cones are not coupled to
cones, they are weakly coupled to adjacent rods. However, our experiments used a light
stimulus with a background intensity that nearly saturated the rod response while prob-
ing the cone response. The very minimal rod responses would be further attenuated by the
strong resistance (weak coupling) between rods and cones [7]. Another potential drawback
of this method is that negative feedback from horizontal cells to cones could lead to an un-
derestimate of the light response profile. However, our experience from other experiments
is that thin bar stimuli such as the one we used to not stimulate enough of the horizontal
cell receptive field to elicit any feedback.

5.7.2 Measurement of coupling via dual-patch

Our dual-patch recordings are the first known set of paired patch-pipette recordings from
adjacent rods in the whole salamander retina. Other studies have used patch pipettes in

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