Colors We See Fade as We Age, Study Finds

The colors we see may get increasingly dull as we get older, scientists have found.

The pupils of younger people's eyes react differently to bright colors than those of older folk, a new paper in the journal Scientific Reports reveals.

"This work brings into question the long-held belief among scientists that color perception remains relatively constant across the lifespan, and suggests instead that colors slowly fade as we age. Our findings might also help explain why our color preferences may alter as we age, and why at least some older people may prefer to dress in bold colors," study author Janneke van Leeuwen said in a statement. She is a neurodegenerative disease researcher at the University College London (UCL) Queen Square Institute of Neurology in the United Kingdom.

The pupil of the eye tends to constrict or get smaller when exposed to bright colors. In the paper, the authors describe how they compared how the pupils of 17 younger and 20 older people reacted to being exposed to 26 different colors for 5 seconds each. The colors included a variety of bright and dull shades, including four greyscale colors, two oranges, and dark, muted, saturated and light shades of magenta, blue, green, yellow and red.

The scientists found that the older people's pupils constricted less to brighter colors than the younger group, especially for green and magenta shades. The reaction to the lightness of a hue was unchanged between age cohorts, however.

"In our study, we looked at how color perception is affected by aging by looking at the effects of the intensity (saturation) and the lightness of colors on pupil responses of healthy young and older adults," van Leeuwen told Newsweek. "The results showed that the pupils of older adults responded the same as young adults to the lightness level of colors but less strongly to the saturation of colors. This suggests that our brains become less sensitive to the intensity of colors in the world around us."

Therefore, the brains of older people can be concluded to be less sensitive to the brightness of colors. This is supported by previous work that found older people see surface color as less colorful than younger adults.

This may be because aging comes with a decline in the primary visual cortex's sensitivity to color saturation. This is a part of the brain that processes visual information from the eyes. A form of dementia known as posterior cortical atrophy (PCA) can result in similar symptoms of difficulty in color perception. This may result from a reduction in the brain's sensitivity to specific colors.

"Pupil responses are not regulated by the eye, but by structures in the midbrain. It has been shown that pupil dynamics are aligned with the transmission of visual information between the retina of the eye and the brain. This means that studying pupil responses to colors can tell us something about how color information is conveyed between the eye and the visual cortex (and higher cortical areas)," van Leeuwen said.

"Our findings could have wide implications for how we adapt fashion, décor and other color 'spaces' for older people, and potentially even for our understanding of diseases of the aging brain, such as dementia. People with dementia can show changes in color preferences and other symptoms relating to the visual brain.

"To interpret these correctly, we first need to gauge the effects of healthy aging on color perception. Further research is therefore needed to delineate the functional neuroanatomy of our findings, as higher cortical areas might also be involved."

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Update 1/24/24, 12:10 p.m. ET: This article was updated with comment from Janneke van Leeuwen.