Research news: dark text on bright background causes myopia.
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| Why Might Reading Make Myopic? |
| from the everyone-switch-to-the-VT220-theme dept. |
| posted by chromas on Sunday October 28, @17:55 (Science) |
|
https://soylentnews.org/article.pl?sid=18/10/28/1449210 |
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[0]upstart writes:
Submitted via IRC for Bytram
[1]Why might reading make myopic?
It is known that myopia develops later when children are more outside
before school and are exposed to bright illumination. What exactly
makes them myopic when they start reading at school is still not
fully understood.
[...] There are cells that respond mostly to brightness in the center
of the receptive fields and darkness in the periphery (ON center
cells), and cells that respond preferentially when the center is dark
and the periphery is bright (OFF center cells). During our normal
daily visual experience, both types are similarly stimulated. But
what happens during reading of text?
Software was developed to quantify the relative stimulus strength for
ON and OFF cells for various visual environments. The software showed
that dark text on bright background stimulates mainly OFF cells
(Figure 1 A), while bright text on dark background stimulates mainly
the ON cells (Figure 1B). It was known from earlier experiments in
chickens and mice that stimulation of ON cells tended to inhibit eye
growth while stimulation of OFF cells tended to increase eye growth.
[...] Using optical coherence tomography (OCT) it is possible to
measure the thickness of tissue layers in the living eye with very
high resolution (micrometer range). The layer behind the retina, the
choroid, is of particular interest since it has earlier been shown in
chickens, various species of monkeys and children that changes in
choroidal thickness can predict future changes in eye growth. When
the choroid thins, the eye typically starts growing, when it
thickens, eye growth is inhibited and no myopia will develop.
Alleman, Wang and Schaeffel asked their subject to read dark text on
white background or bright text on dark background. Already after 30
minutes it was found that the thickness of the choroid either
decreased (when reading standard text) or increased when reading text
with inverted contrast (Figure 2). One would therefore expect that
dark text on bright background would stimulate myopia development and
bright text on dark background would inhibit myopia. Simply inverting
text contrast is therefore strategy to inhibit its development. This
is easily achieved on computer screens and tablets but certainly more
demanding when it comes to printed books.
Reading and Myopia: Contrast Polarity Matters (DOI:
[2]10.1038/s41598-018-28904-x)
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[3]Original Submission
Discuss this story at:
https://soylentnews.org/comments.pl?.../10/28/1449210
Links:
0.
https://soylentnews.org/~upstart/
1.
http://www.eye-tuebingen.de/the-inst...g-make-myopic/
2.
https://doi.org/10.1038/s41598-018-28904-x
3.
https://soylentnews.org/submit.pl?op...ub&subid=29782