EYE STRAIN, IRRITATION AND BLINK RATE RESEARCH


RESEARCH 


EYE STRAIN, IRRITATION AND BLINK RATE RESEARCH

  • The Vision Council, Hindsight: Protect Your Eyes from Digital Devices
    • More than 90% of adults spend more than two hours on computer, leading to eye strain. On average, person blinks 18 times per minute. Using screens causes blink rates to drop, resulting in dry, itchy or burning eyes. HEV light reaches deeper in the eye which may damage the retina. Research points to link between blue light and long term vision issues including AMD and cataracts.
  • Mayo Clinic: Eyestrain Causes and Digital Eye Strain Symptoms
    • Extended us of a computer or digital device can lead to digital eye strain in the form of sore, tired, burning eyes, dry eyes, blurred or double vision and headaches.
  • Optometry Times: How Digital Devices are Affecting Your Vision
    • Prolonged exposure to digital devices leading to digital eye strain including eye strain, redness and dryness due to decreased blinking, blurry vision due to glare and headaches. UV from devices contributor to cataracts and AMD.
  • Optometry and Vision Science: Effect of Visual Display Unit on Blink Rate and Tear Stability
    • In normal healthy subjects, the results show an average 5-fold drop in blink rate during VDU use but tear stability appears to be unaffected. During VDU use a significant relation was found to exist between the interval between blinks and the stability of the precorneal tear film.

 SLEEP AND DISRUPTION OF CIRCADIAN RHYTHMS

  • Harvard Medical School: Blue Light Has a Dark Side
    • Blue light exposure association with acute retinal injury, aging of the retina, age related macular degeneration, melatonin suppression. Harvard study shows nighttime device exposure suppressing melatonin and disruption of circadian rhythm.
  • The Journal of Neuroscience: Action Spectrum for Melatonin Regulation in Humans
    • Exposure to light from self-luminous displays may be linked to increased risk for sleep disorders because these devices emit optical radiation at short wavelengths, close to the peak sensitivity of melatonin suppression
  • National Center for Biotechnology Information: Light Level and Duration of Exposure
    • Exposure to devices linked to increased risk for sleep disorders and melatonin suppression because of short wavelength emissions.
  • Penn State University: Use of eReaders Negatively Affects Sleep, Circadian timing, and alertness
    • The use of digital devices before bedtime prolongs the time it takes to fall asleep, delays the circadian clock, suppresses levels of the sleep-promoting hormone melatonin, reduces the amount and delays the timing of REM sleep, and reduces alertness the following morning.
  • S. National Library of Medicine: The Unique Health Effects of Blue Light
    • Blue light exposure can disrupt circadian rhythms

OCULAR HEALTH, AMD AND CATARACTS

  • Environmental Health Perspectives: LEDs and Retinal Injury in a Rat Model
    • The results of the present study indicate that exposure to LED light in this albino rat model can induce retinal damage as evidenced by the functional ERG study, IHC, TUNEL, and TEM examinations. Our results also suggest that this retinal damage could be related to blue light–induced oxidative stress within the retinal tissues, as evidenced by the ROS generated in the retina after LED light exposure; blue light exposure may cumulatively induce photoreceptor loss.
  • PECAA: HEV and Potential Ocular Damage
    • Studies have shown that deeper blue frequencies similar to what we are exposed to with LED from tablets and smartphones are 50-80 times more efficient in causing photoreceptor death than green light. Paris study showed a 25x greater potential of retinal receptor damage over time.
  • Progress in Retinal and Eye Research: LED Light: Any Risks for the Eye?
    • This is the first time the human population will be exposed to such substantial blue light. Such retinal exposure may induce macular degeneration, glaucoma neuropathy and circadian rhythm disruption. Although the white light generated from LEDs appears normal to human vision, a strong peak of blue light ranging from 460 to 500 nm is also emitted within the white light spectrum; this blue light corresponds to a known spectrum for retinal hazards.
  • Review of Optometry: The Lowdown on Blue Light
    • UV and HEV light from devices damaging retina, associated with age related macular degeneration, formation of cataract cell life, damage to retinal cells. HEV/blue light impacting back of the eye (AMD) while UV impacting front of eye (cataract formation).
  • Optometric Management: Shedding Light on the Blue Light Spectrum
    • Blue light scientifically recognized as harmful to the retina. Numerous in vitro and vivo studies provide evidence of the blue light toxicity on the RPE and photoreceptor cells. May irreversibly alter the retina.
  • American Macular Degeneration Foundation: Protect Your Eyes from Harmful UV and Blue Light
    • UV light harmful to the eye and may lead to cataracts and other eye diseases such as AMD. Studies suggest blue light spectrum contributes to retinal damage.
  • Schepens Eye Institute: Blue Light Increases Risk of AMD (Light Cues)
    • Blue rays of the spectrum seem to accelerate AMD more than other rays in the spectrum. Blue light directly penetrates the macular pigment of the eye, causing retinal damage.
  • Paris Vision Institute & ESSILOR: Blue Light: The Hazard and the Photoprotection Challenge
    • The most energetic light reaching the retina is blue light. The band of blue light most harmful to the retina found to be 415 to 455 nm.
  • Fundacion Mapfre: Personal Risks Posed by LEDS in Everyday Devices
    • Scientifically proven that blue light has negative effects on the eye. Exposure to LED light, especially in shorter wavelengths, harms retinal pigment epithelium cells.
  • American Printing House for the Blind: The Effects of Blue Light on Ocular Health
    • Association between cataract formation and exposure to UV-B and potential link to AMD, and destruction of cells in the center of the retina.
  • S. National Library of Medicine: Photochemical Damage of the Retina
    • Photochemical mechanisms, in particular mechanisms that arise from illumination with blue light, are responsible for solar retinitis and for iatrogenic retinal insult from ophthalmological instruments. Further, blue light may play a role in the pathogenesis of age-related macular degeneration.
  • S. National Library of Medicine: Effects of LED radiation on Human Retinal Pigment Epithelial Cells in Vitro
    • It is shown that LED radiations decrease 75-99% cellular viability, and increase 66-89% cellular apoptosis. They also increase ROS production and DNA damage.

Excerpts

  • “Nearly 70% of American adults experience some form of digital eye strain due to prolonged use of electronic devices" (Vision Council 2014).
  • “Many current “white-light” LED designs emit much more blue light than conventional lamps, which has a number of health implications, including disruption of circadian rhythms (Holzman 2010). The most popular LED lighting product, a phosphor-conversion (PC) LED, is an LED chip that emits blue light, which passes through a yellow phosphor-coating layer to generate the ultimate white light (Spivey 2011).
  • Although the white light generated from LEDs appears normal to human vision, a strong peak of blue light ranging from 460 to 500 nm is also emitted within the white light spectrum; this blue light corresponds to a known spectrum for retinal hazards (Behar-Cohen et al. 2011).
  • Some epidemiological studies have suggested that short-wavelength light exposure is a predisposing cause for age-related macular degeneration (AMD) (Wu et al. 2006).
  • Animal models have also been used to determine that excessive exposure to blue light is a critical factor inphotochemical retinal injury targeting photoreceptors and the retinal pigment epithelium (RPE) (Hafezi et al. 1997).” 
  • “Exposure to light from self-luminous displays may be linked to increased risk for sleep disorders because these devices emit optical radiation at short wavelengths, close to the peak sensitivity of melatonin suppression.” 

Ds appears normal to human vision, a strong peak of blue light ranging from 460 to 500 nm is also emitted within the white light spectrum; this blue light corresponds to a known spectrum for retinal hazards (Behar-Cohen et al. 2011)
Some epidemiological studies have suggested that short-wavelength light exposure is a predisposing cause for age-related macular degeneration (AMD) (Wu et al. 2006)
Animal models have also been used to determine that excessive exposure to blue light is a critical factor inphotochemical retinal injury targeting photoreceptors and the retinal pigment epithelium (RPE) (Hafezi et al. 1997).”
“Exposure to light from self-luminous displays may be linked to increased risk for sleep disorders because these devices emit optical radiation at short wavelengths, close to the peak sensitivity of melatonin suppression.”