The human eyes are color blind at night: two views of the Milky Way
The photoreceptors neurons in the retina comprise rods and cones. They are capable of transforming light stimulus into a nerve impulse, which subsequently conducted by the optic nerve to the occipital cortex. The rods function only in dim light and are not sensitive to colour whereas the cones respond well to bright light and are sensitive to colour.
The macula is responsible for best visual acuity and for colour vision; most of its photoreceptors are cones. Rods are absent at the centre of the macula, it is situated more at the peripheral and the primary function of the rods is for peripheral and night vision. (copied from article)
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