Digital eye strain is a set of ocular and neurological discomforts that occur after prolonged exposure to screens that emit artificial light, especially LED. It manifests as eye fatigue, blurred vision, burning, light sensitivity, and difficulty maintaining concentration.
Screens emit high-energy blue and green light that increases stress on the retina, reduces blinking, alters the stability of tears, and forces the eye to maintain close focus for long periods. When this exposure is repeated without protective measures, visual fatigue can intensify and become a persistent issue.
Dryness and eye irritation indicate a disruption of the tear film, which loses stability and leaves the surface of the eye exposed. This causes symptoms such as stinging, redness, unstable vision, and the sensation of a foreign body.
Prolonged use of screens interferes with the eye's natural defense mechanisms: it reduces blinking, accelerates tear evaporation, and increases oxidative stress from exposure to blue and green light. If this aggression is repeated daily, the eye loses the ability to recover, and irritation can become chronic, increasing the risk of developing dry eye syndrome in the long term.
The headaches associated with the use of screens are not coincidental; they are classified as functional headaches and are the direct result of an overload of the visual and neurological system. It is not just simple fatigue, but a defensive response of the nervous system to a visual stimulus that it perceives as too intense and sustained to be processed naturally.
In people with a certain predisposition, this overstimulation acts as a switch that can trigger or worsen migraine episodes, generating a hypersensitivity to light (photophobia) that makes it almost impossible to continue in front of the monitor.
Why does the screen act as a trigger? The problem is not just staring at something, but rather what we are looking at and how. Prolonged exposure to digital devices creates a "perfect storm" of stressors for the brain:
• Continuous blue light emission: High-energy light acts as a powerful neurological activator, saturating the visual pathways.
• Unending stimulation: We maintain a close and constant focus, without the natural pauses that the eye would have in an analog environment.
• Activation of pain areas: This sustained effort ultimately leads to excessive activation of the brain areas involved in the perception of pain.
The alterations in sleep caused by screens go far beyond "not feeling sleepy" when it's time to go to bed. It is a deep deregulation of the circadian rhythm, the internal clock that dictates to our body when it should be active and when it should rest. The problem does not only lie in sleeping fewer hours, but in sleeping worse.
The use of devices, especially in the moments prior to rest, fragments the architecture of sleep, causing late onset of sleep, nighttime awakenings, and a feeling of unrefreshing sleep the next day.
Consequences of an interrupted rest When this light interference becomes a nightly habit, the deficit of rest accumulates. The difficulty in falling asleep is no longer a one-time issue; it affects the depth and quality of sleep, reducing the phases of restorative sleep. The result is accumulated daytime fatigue that compromises performance, memory, and concentration the following day. It is important to note that this impact is even more severe in children and adolescents, whose circadian system is still developing and is more sensitive to these interruptions.
Unlike visual fatigue, which signals with immediate discomfort, long-term eye damage is a silent and cumulative process that does not always present obvious symptoms at first. It is directly associated with repeated and prolonged exposure to high-energy light (blue spectrum and part of the green spectrum), which acts day after day on our eyes.
Current studies indicate that, although screen use does not cause diseases immediately, it does promote biological conditions that increase the risk of suffering irreversible retinal damage, especially in situations of high daily exposure.
