Shelby Temple, PhD, a visual neuroscientist, has spent the last two decades investigating the way the visual system detects and responds to light.
He began his research looking at polarized light detection in cuttlefish, a species whose vision does not identify color wavelengths of light but whose vision depends on detecting different polarizations of light. In the process of his research, he looked at polarization detection in humans. He learned that the mechanism by which humans can perceive polarized light is caused by molecular components in the retina that protect the eye from high-energy blue wavelength light. He has devoted his career to researching and educating the public about blue light science and the impact it can have on ocular health.
Do digital devices really put our eyes at risk? This is the question that Dr. Temple is most commonly asked when he speaks with eyecare professionals.
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“On their own, individual devices probably aren’t putting out high enough amounts of energy that they are going to cause immediate damage,” Dr. Temple says. “But in the long-term, that’s more interesting. It’s not about the intensity; it’s about the exposure.”
Length of time of the computer, dilation of the pupil during device use—these factors could make a difference over a lifetime of blue light exposure.
Animal model research
One thing Dr. Temple feels strongly about is that the existing blue light research done on animal models should not be disregarded.1-5 Animal studies have long been used to explore how the human body works and are important when investigating long-term, chronic conditions like retinal damage from blue light exposure where it would be impossible to follow candidates for 65+ years and control for environment and medical history.
“This type of study is not feasible; it’s never going to happen,” he says. “What we can do is look at animal studies and epidemiological studies in humans, and all of these studies show without question that blue light can damage the retina.”
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