May 9, 2013
Brain, Not Eye Mechanisms Keep Color Vision Constant Across Lifespan
Optical media changes with age, but neural mechanisms keep color perception constant
Cone receptors in the human eye lose their color sensitivity with age, but our subjective experience of color remains largely unchanged over the years. This ability to compensate for age-related changes in color perception rests in higher levels of the visual system, according to research published May 8 in the open access journal PLOS ONE by Sophie Wuerger from the University of Liverpool, UK.The study included 185 participants aged 18 to 75 years with normal color vision, and revealed that the appearance of color remains largely unaffected by known age-related changes in the optical media within the lens, but the ability to distinguish between small differences in shades of colors decreases with increasing age, particularly for colors on the yellow-blue axis. The effects of age were most apparent when participants viewed shades of green in daylight- what appeared uniquely green to younger observers appeared more yellowish to older viewers. The author concludes that certain neural pathways compensate for age-related losses in the eye, so color functions remain largely constant over time.
"We found that color vision remains fairly constant across the life span, despite the known age-related yellowing of the lens," says Wuerger. "This suggests that the visual brain re-calibrates itself as we get older."
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