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Vision changes as we age
Vision changes are inevitable
 Vision changes are one of the more undeniable signs of aging. These
changes in vision usually occur between the ages of about 40 to 50,
with most people noticing more difficulty seeing objects closer than 2
feet as they age. This change in vision is referred to as
presbyopia which occurs as the lens of the eye begins to stiffen.
In normal cases a lens changes its shape to help people focus their
eyes. When the lens stiffens, it cannot easily focus on objects that
are up close.
Many people try to ignore presbyopia as long as they possibly can.
Ultimately however, almost everyone with presbyopia eventually will
need some type of reading glasses. People who are nearsighted or have
problems seeing objects in the distance may need to wear bifocals, or
glasses with variable focus lenses.
As people continue to age, vision also changes in other ways.
Frequently it becomes more difficult to see in dim light. Light
passes through the lens to the retina on the back of the eye, but as
the lens becomes denser you actually have less light entering the eye.
The retina contains cells that sense light which then becomes less
sensitive. More light then becomes necessary for activities such as
reading. On the average, a 60-year-old needs about three times more
light to read than a 20-year-old.
Vision is also affected significantly by the reactions of the pupil of
the eye as we age. Research continues to find that as we age the pupil
of the eye reacts much more slowly to changes in light. Light is
allowed to enter through the pupil (which widens or narrows) much more
slowly letting more or less light in. As result, older people may be
unable to see when they first enter a dark room for a longer period of
time. Or, they may also be temporarily blinded when they enter a very
brightly lit area. This effect is most noticeable during such
experiences as when an older person leaves a dark theater or may enter
or exit a tunnel while driving. Older eyes are less able to adjust
partly because the muscles that expand and contract in people tend to
weaken as they age. Older individuals may also become much more
sensitive to glare. However, more frequently, increased sensitivity
to glare is usually due to eye disorders such as cataracts.
Changes in color vision:
Color vision may also change as people age. Colors may actually be
perceived differently by older people. This change occurs frequently
because the lens tends to yellow slightly with the aging process.
Yellowing affects how colors at the blue-violet end of the light
spectrum are viewed. Blues tend to be less vivid and look more like
gray. This change is not a huge problem for most people. However,
older people may have trouble reading black letters on a blue
background or reading blue letters in general. Usually at the other
end of the color spectrum however, reds tend to be much more vivid.
The ability to see differences in shades and tones and also to see
fine details decreases. Vision experts usually attribute this change
to the fact that the number of nerve cells of the brain used to
transmit visual signals from the eyes to the brain decreases. This
change affects the way depth is perceived and judging distances
becomes much more difficult.
A minor irritant for older people may be floaters. Floaters are tiny
black specks moving across your field of vision. The specks are bits
of fluid within the eye that have solidified. Floaters do not
significantly interfere with vision however. Unless they increase in
a significant amount they are not usually of concern.
Some information from The Merck Manual of Healthy Aging
Additional information and web page by
Paul Susic M.A. Licensed
Psychologist Ph.D. Candidate (Health Psychology)
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