The retina contains several layers of nerves that seem to encode light into neural signals. But no-one had been able to crack the code that enables the brain to 'see'. With the new device, rather than feeding visual signals directly into the eye, they processed them using a code that the researchers had developed by watching how a healthy retina responds to stimuli. After receiving the encoded input, the mice were able to track moving stripes, something that they hadn't been able to do before (abstract)."
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