Gaby
As we age, the world around us changes along with our bodies. Our senses of taste, smell, hearing, and sight all become less sharp. A new study shows that, over the years, the colors around us can start to look faded.
It turns out that as we get older, our sensitivity to color diminishes. But that decline doesn’t affect every hue the same way.
A recent study by a team from University College London (UCL) helps explain why some older adults suddenly start wearing very bright clothes.
What the Researchers Discovered
The team compared how younger and older people reacted to different colors. The experiment included 17 younger participants (average age 27.7 years) and 20 healthy older adults (average age 64.4 years). Participants sat in a dimly lit room and were shown 26 different colors, each for five seconds. During the test, researchers measured the volunteers’ pupil diameter with a highly sensitive device called a pupillometer.
Participants saw dark, muted, saturated, and light shades of purple, blue, green, yellow, and red, plus two shades of orange and four shades of gray.
Normally, when we look at a color, our pupils constrict in response to changes in brightness or saturation. Using the pupillometer, the team recorded pupil-diameter changes at a rate of 1,000 times per second.
From the pupillometry data, the researchers found that pupils in healthy older adults constricted less in response to color saturation than those of younger participants. IFLScience reported that this difference was especially noticeable for greens and purples. By contrast, sensitivity to saturation in lighter shades and in blue stayed the same in the older group.
In their report the team wrote, “With age, we become physiologically less sensitive to the colorfulness of our environment. We hypothesize that colors fade with age and that we become less sensitive to the saturation levels of green or purple colors.”
Dr. Janneke van Leeuwen, the study’s lead author, said, “This work challenges the long-held belief that color perception remains relatively constant throughout life. Colors gradually fade with age.”
Why This Happens
The researchers think the drop in sensitivity to color saturation happens in the primary visual cortex, the part of the brain that receives, integrates, and processes visual information from the retina.
A previous study found similar changes in a rare form of dementia called posterior cortical atrophy (PCA). That condition produces changes in color perception that may stem from a decline in the primary visual cortex’s sensitivity to certain tones. Those changes primarily affect greens and purples.
The findings were published in the journal Scientific Reports.
