The name is absent

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With the cone model, we investigate a potential component of horizontal cell to cone
feedback that is common to both the pH and hemichannel theories of feedback. We con-
clude that this mechanism, which involves activation of voltage gated calcium channels and
gating of a calcium activated chloride current, is feasible (section 4.2.1). This analysis also
suggests that modulation of the calcium current alone is not enough to cause the observed
depolarization during a horizontal cell surround response, highlighting the potential role
for the calcium activated chloride current in the feedback response.

Finally, in chapter 5, we perform a detailed analysis of rod-rod coupling using light and
electrical stimuli, and use the resulting parameters in a linear model of the rod network.
With the model, we demonstrate quantitatively how rod-rod coupling leads to an attenua-
tion of high spatial frequencies in visual scenes, but also a large reduction in photoreceptor
noise. By analyzing the tradeoffbetween these two features, we show that coupling provides
a benefit in signal-to-noise ratio for most perceptible stimuli. This benefit is especially help-
ful in the representation of natural scenes, a task for which the rod system has presumably
evolved to handle.

I hope that these studies will provide a base for further studies of the retina by others
in the field of retinal physiology. In particular, the analysis in chapter 5 is not necessarily
specific to rods, and could be generalized to other coupled neurons in the retina.

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