 0\) I was confused by how the retinal functional measurements are clustered and categorised. The authors say they identified 00 groups (subsection "Functional classes of retina ganglion cells show refined pathway selectivity") but do not say how these were identified. For example, it is not clear to me why Group (ii) is a sustained OFF cell when the onset response appears transient, and on what basis it is distinguished from Group (iv). Some more explanation of the response to these stimuli would be useful; claims of functional differentiation between cells, and therefore whether or not particular functional classes project to particular brain areas, would also seem to require statistical support.  