Growth and Development Q 40
When caring for an elderly client it is important to keep in mind the changes in color vision that may occur. What colors are apt to be most difficult for the elderly to distinguish?
A. Red and blue
B. Blue and green
C. Red and green
D. Blue and gold
Correct Answer: B. Blue and green
The elderly have poor blue-green discrimination. The effects of age are greatest on short wavelengths. These changes are related to the yellowing of the lens with age. Nearly 80 percent of the abnormalities involved confusion of the lighter (pastel) shades of blue versus purple and yellow versus green and yellow-green. These “blue-yellow” errors are distinct from the “red-green” errors observed in people with inherited color blindness, which affects about eight percent of males and 0.5 percent of females.
Option A: The elderly are better able to distinguish between red and blue because of the difference in wavelengths. Cells in the retina that are responsible for normal color vision decline in sensitivity as people age, causing colors to become less bright and the contrast between different colors to be less noticeable.
Option C: Red-green color vision deficiencies occur when there are defects with the OPN1LW (red pigment cone) and OPN1MW (green pigment) genes. These affect the way that color wavelengths are detected by the cones in the retina. Red and green color blindness is an inherited disorder that is unrelated to age. Red-green color blindness is typically caused by genetic mutations.
Option D: The elderly are better able to distinguish between blue and gold because of the difference in wavelengths. Blue-yellow color vision defects affect males and females equally. This condition occurs in fewer than 1 in 10,000 people worldwide. Blue cone monochromacy is rarer than the other forms of color vision deficiency, affecting about 1 in 100,000 people worldwide.