Do retinal ganglion cells project natural scenes to their principal subspace and whiten them?

Understand

Several theories of early sensory processing suggest that it whitens sensory stimuli.

• Here, we test three key predictions of the whitening theory using recordings from 152 ganglion cells in salamander retina responding to natural movies.
• We confirm the previous finding that firing rates of ganglion cells are less correlated compared to natural scenes, although significant correlations remain.
• We show that while the power spectrum of ganglion cells decays less steeply than that of natural scenes, it is not completely flattened.