Scientists at the University of Liverpool have found that the human brain may be able to compensate for the age-related decline in the eye’s ability to distinguish subtle differences between colours.
Cone receptors in the human eye lose their sensitivity and the lens absorbs more bluish light as the body ages. This can lead to loss of ability to discern the difference between colours.
The subjective experience of colour, however, remains largely unchanged over the years. New research at Liverpool suggests that the ability to compensate for age-related changes in the optical media is likely to reside in higher levels of the visual system.
Age-related changes
The study included 185 participants aged 18 to 75 years with normal colour vision, and revealed that the appearance of colour remains largely unaffected by known age-related changes in the lens. The ability to distinguish between small differences in shades of colours, however, decreases with increasing age, particularly for colours on the yellow-blue axis.
Dr Sophie Wuerger, from the University’s Institute of Psychology, Health and Society, concluded that certain neural pathways compensate for age-related losses in the eye, and therefore some colour functions remain largely constant over time.
Dr Wuerger said: “We found that colour vision remains fairly constant across the lifespan, despite the known age-related yellowing of the lens. This suggests that the visual brain re-calibrates itself as we get older.”
“To understand the time-course of this re-calibration mechanism and which visual functions are able to benefit from this compensatory process, we are planning a follow-on study with individuals before and after cataract surgery.”
The research was published in the journal PLoS One.
