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Impact of Computer Use on Children's Vision |
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When first introduced, computers were almost
exclusively used by adults. Today, children increasingly use these
devices both for education and recreation. Millions of children use
computers on a daily basis at school and at home.
Children can experience many of the same symptoms related to
computer use as adults. Extensive viewing of the computer screen can
lead to eye discomfort, fatigue, blurred vision and headaches.
However, some unique aspects of how children use computers may make
them more susceptible than adults to the development of these
problems.
The potential impact
of computer use on children's vision involves the
following factors:
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Children often have a limited degree of
self-awareness |
Many
children keep performing
an enjoyable task with
great concentration
until near exhaustion
(e.g., playing video
games for hours with
little, if any, breaks).
Prolonged activity
without a significant
break can cause eye
focusing (accommodative)
problems and eye
irritation.
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Accommodative problems may occur as a result of
the eyes' focusing system "locking in" to aspecialtarget and
viewing distance. In some cases, this may cause the eyes to be
unable to smoothly and easily focus on aspecialobject, even
long after the original work is completed.
Eye irritation may occur because of poor tearflow over the eye due
to reduced blinking. Blinking is often inhibited by concentration
and staring at a computer or video screen. Compounding this,
computers usually are located higher in the field of view than
traditional paperwork. This results in the upper eyelids being
retracted to a greater extent. Therefore, the eye tends to
experience more than the normal amount of tear evaporation resulting
in dryness and irritation.
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Children are very adaptable |
Although there are many
positive aspects to
their adaptability,
children frequently
ignore problems that
would be addressed by
adults. A child who is
viewing a computer
screen with a large
amount of glare often
will not think about
changing the computer
arrangement or the
surroundings to achieve
more comfortable
viewing. This can result
in excessive eye strain.
Also, children often
accept blurred vision
caused by
nearsightedness
(myopia), farsightedness
(hyperopia), or
astigmatism because they
think everyone sees the
way they do. Uncorrected
farsightedness can cause
eye strain, even when
clear vision can be
maintained.
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Children are not the same size as adults. |
Since
children are smaller,
computers don't fit them
well. Most computer
workstations are
arranged for adult use.
Therefore, a child using
a computer on a typical
office desk often must
look up further than an
adult. Since the most
efficient viewing angle
is slightly downward
about 15 degrees,
problems using the eyes
together can occur. In
addition, children may
have difficulty reaching
the keyboard or placing
their feet on the floor,
causing arm, neck or
back discomfort.
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Children often use computers in a home or
classroom with less than optimum lighting |
The
lighting level for the
proper use of a computer
is about half as bright
as that normally found
in a classroom.
Increased light levels
can contribute to
excessive glare and
problems associated with
adjustments of the eye
to different levels of
light.
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Steps
to Visually-Friendly Computer Use
Here are some things to consider for children using a
computer
Children have different needs to comfortably use a
computer. A small amount of effort can
help reinforce appropriate viewing habits and assure
comfortable and enjoyable computer use. |
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Have the child's vision checked. This will make
sure that the child can see clearly and comfortably and
can detect any hidden conditions that may contribute to
eye strain. When necessary, glasses, contact lenses or
vision therapy can provide clear, comfortable vision,
not just for using the computer, but for all other
aspects of daily activities.
Strictly enforce the amount of time that a child can
continuously use the computer. A ten-minute break
every hour will minimize the development of eye focusing
problems and eye irritation caused by improper blinking.
Carefully check the height and arrangement of the
computer. The child's size should determine how the
monitor and keyboard are positioned. In many situations,
the computer monitor will be too high in the child's
field of view, the chair too low and the desk too high.
A good solution to many of these problems is an
adjustable chair that can be raised for the child's
comfort, since it is usually difficult to lower the
computer monitor. A foot stool may be necessary to
support the child's feet.
Carefully check the lighting for glare on the
computer screen. Windows or other light sources
should not be directly visible when sitting in front of
the monitor. When this occurs, the desk or computer may
be turned to prevent glare on the screen. Sometimes
glare is less obvious. In this case, holding a small
mirror flat against the screen can be a useful way to
look for light sources that are reflecting off of the
screen from above or behind. If a light source can be
seen in the mirror, the offending light should be moved
or blocked from hitting the screen with a cardboard hood
(a baffle) attached to the top of the monitor. In
addition, the American Optometric Association has
evaluated and accepted a number of glare screens that
can be added to a computer to reduce glare. Look for the
AOA Seal of Acceptance when purchasing a glare reduction
filter.
Reduce the amount of lighting in the room to match
the computer screen. Often this is very simple in
the home. In some cases, a smaller light can be
substituted for the bright overhead light or a dimmer
switch can be installed to give flexible control of room
lighting. In other cases, a three-way bulb can be turned
onto its lowest setting.
Children have different needs to comfortably use a
computer. A small amount of effort can help reinforce
appropriate viewing habits and assure comfortable and
enjoyable computer use. |
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