Abstract:
:Under natural viewing conditions the input to the retina is a complex spatiotemporal signal that depends on both the scene and the way the observer moves. It is commonly assumed that the retina processes this input signal efficiently by taking into account the statistics of the natural world. It has recently been argued that incessant microscopic eye movements contribute to this process by decorrelating the input to the retina. Here we tested this theory by measuring the responses of the salamander retina to stimuli replicating the natural input signals experienced by the retina in the presence and absence of fixational eye movements. Contrary to the predictions of classic theories of efficient encoding that do not take behavior into account, we show that the response characteristics of retinal ganglion cells are not sufficient in themselves to disrupt the broad correlations of natural scenes. Specifically, retinal ganglion cells exhibited strong and extensive spatial correlations in the absence of fixational eye movements. However, the levels of correlation in the neural responses dropped in the presence of fixational eye movements, resulting in effective decorrelation of the channels streaming information to the brain. These observations confirm the predictions that microscopic eye movements act to reduce correlations in retinal responses and contribute to visual information processing.
journal_name
Proc Natl Acad Sci U S Aauthors
Segal IY,Giladi C,Gedalin M,Rucci M,Ben-Tov M,Kushinsky Y,Mokeichev A,Segev Rdoi
10.1073/pnas.1412059112subject
Has Abstractpub_date
2015-03-10 00:00:00pages
3110-5issue
10eissn
0027-8424issn
1091-6490pii
1412059112journal_volume
112pub_type
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