Visual Stress in Virtual Learning: What to Watch For

Remote classes, hybrid days and homework that lives on a laptop changed what a school day asks of a child’s eyes. In a classroom, a child looks up at a board, down to a notebook, over at a neighbor — dozens of times an hour, without thinking about it. On a video class that variety disappears: one screen, one working distance, sometimes six or seven hours a day.

For most children that is tiring but manageable. The children we end up seeing are usually the ones whose eyes do not aim, focus or track easily. Our clinical impression is that a screen day takes away the small breaks that used to hide the problem. For age-by-age limits, see our companion guide, How Much Screen Time Is Too Much? This article stays on visual stress.

Key takeaways

• Near work asks three skills at once — aiming, focusing and tracking — and a screen holds all three at one distance for hours.
• Binocular problems are common at school age: 13% of fifth- and sixth-graders met a convergence insufficiency definition in one US school study (Rouse et al., 1999).
• Digital eye strain comes in two forms — dry-eye irritation and focusing effort — and affects half or more of computer users (Sheppard & Wolffsohn, 2018).
• Pandemic home schooling coincided with a myopic shift of about -0.3 D in a 123,535-child screening study (Wang et al., 2021) — a signal about indoor life, not proof about tablets.
• Working distance, real breaks and time outdoors are worth the effort. Blue-light glasses are not supported for eye strain (Singh et al., 2023).

What a screen asks of a child’s eyes

Every time we look at something close, three things happen together. Both eyes point at exactly the same place, or the image doubles. The focusing system makes that place clear and holds it there. And the eyes move accurately along a line of text without losing the place.

For most adults this is effortless. For a meaningful minority of children it is not. In a US school study of fifth- and sixth-graders, 13% met a high-suspect or definite definition of convergence insufficiency, and 78.9% of the children with three-sign CI also had a focusing problem (Rouse et al., 1999). Among 920 schoolchildren in India, non-strabismic binocular vision anomalies ran about 30%, convergence insufficiency was the most common, and rates were higher in teenagers (Hussaindeen et al., 2017). Different populations, different cut-offs, same message: this is not rare.

The diagram at the top of this article shows what that looks like on the page. When both eyes point at the same word, the sentence stays single and clear. When they do not team accurately, the same sentence doubles and overlaps.

Virtual school does not create those problems. We are not aware of a study that has tested this directly, but in our offices the pattern is consistent: remove the relief, and a visual system that was quietly working overtime finally runs out of room.

The symptoms parents notice first

Digital eye strain has two halves. External symptoms — burning, dryness, grittiness, watering — come mostly from a blink rate that drops during concentrated screen work. Internal symptoms — aching behind the eyes, headache, blur when looking up — come from sustained focusing and eye-teaming effort (Sheppard & Wolffsohn, 2018; Rosenfield, 2011). A 2024 meta-analysis of 103 studies and 66,577 participants pooled a prevalence of 69%, though with extreme heterogeneity and mostly adult samples (Ccami-Bernal et al., 2024). Our computer vision syndrome page explains what we test.

In children the report is usually behavioral rather than visual. In our offices we see two patterns:

• The child who compensates. Grades stay fine, sometimes excellent, but the effort behind them is enormous. These children rarely complain, because they have no idea anyone else’s eyes work differently.
• The child who avoids. Homework becomes a fight, reading is “boring,” assignments take three times as long as they should. The ordinary response to something uncomfortable is to avoid it, and vision is no exception.

This is the part parents find hardest to hear: a child who has always seen doubled or blurry print at near assumes everyone does, so the symptom arrives as behavior rather than a complaint.

Screens, myopia and what the data say

Myopia is rising worldwide, with a widely cited projection putting it near half the global population by 2050 (Holden et al., 2016). The clearest pandemic-era signal came from photoscreenings of 123,535 Chinese children aged 6 to 13: 2020 showed a myopic shift of about -0.3 D against 2015-2019, and myopia prevalence at age 6 was 21.5% against a 5.7% high in those earlier years — nearly four times as many six-year-olds (Wang et al., 2021). The authors urged caution — the screenings were non-cycloplegic, and confinement changed far more than screen time.

Screens alone are a weaker signal than headlines suggest. A 2020 review covered 15 studies and 49,789 children; seven of the 15 did report an association, but when the five studies reporting odds ratios were pooled (20,889 children) the result was OR 1.02 (95% CI 0.96-1.08) — effectively nothing (Lanca & Saw, 2020). A 2021 meta-analysis found a modest one — OR 1.26 for smart devices, 1.77 with computer use included — again with high heterogeneity (Foreman et al., 2021). Our reading: hours indoors at close range matter more than which device is doing the work. More in Screen Time and Kids.

A virtual-school set-up that helps

Fix the working distance. Set-up advice rather than a research finding: a laptop or monitor at roughly arm’s length asks less of the focusing and aiming systems than a phone or tablet held close to the face, because the demand on both rises as the working distance shortens. Screen slightly below eye level, back supported, feet on the floor or a box.

Light the room, not just the screen. A bright screen in a dark room makes the eyes work across a large contrast difference. This is comfort advice from clinical experience, not a research finding.

Take breaks, but treat 20-20-20 as a habit, not a prescription. When 30 young subjects — not children — did a 40-minute tablet reading task with 20-second breaks every 5, 10, 20 or 40 minutes (the last being no break at all), there was no significant difference in symptoms, reading speed or accuracy (Johnson & Rosenfield, 2023). Break-reminder software given to 29 symptomatic computer users did improve dry-eye and eye-strain symptoms over two weeks, but the gains faded once the reminders stopped (Talens-Estarelles et al., 2023). Build breaks in anyway, and make them real: stand up, walk to a window, look at something genuinely far away.

Get outside between classes. The best-evidenced item on the list. A meta-analysis of 25 articles found outdoor time protective against developing myopia — risk ratio about 0.54 in trials — though it did not slow progression in eyes already nearsighted (Xiong et al., 2017). In South Florida we have fewer excuses than most.

Skip the blue-light lenses. A 2023 Cochrane review of 17 randomized trials found blue-light-filtering lenses may not reduce eye-strain symptoms compared with standard lenses (Singh et al., 2023).

When to have your child evaluated

If you answer yes to any of these, it is worth having your child examined rather than waiting for the next school year.

• Do you have concerns about your child’s reading abilities?
• Does your child skip lines or words when reading?
• Does your child struggle to keep their attention on reading?
• Does your child have better comprehension when someone reads to them?
• Is homework a struggle?
• Does your child have difficulty completing assignments in a reasonable amount of time?
• Do you have concerns about your child’s reversals of letters or numbers?
• Does your child have frequent headaches or eye discomfort while reading or doing homework?

A distance letter chart does not measure aiming, focusing or tracking. The AOA’s pediatric guideline cites studies finding that acuity testing alone missed 75.5% of children shown on complete examination to have binocular and oculomotor problems, and that only 38.7% of children who failed a screening received follow-up care; on that basis it recommends a comprehensive eye examination before first grade and annually after (AOA, 2017). That annual schedule is the optometric position. The US Preventive Services Task Force, working from screening evidence, recommends vision screening at least once between ages 3 and 5 to catch amblyopia and its risk factors and finds the evidence insufficient below age 3 (USPSTF, 2017). The two bodies are answering different questions — screening for amblyopia, versus measuring how the eyes work together at near. Our symptom checklist is a reasonable first pass at home.

One honest note. Correcting a focusing or eye-teaming problem makes near work more comfortable, which is worth having. It is not a reading intervention: the largest trial to test that question found office-based vergence and accommodative therapy no better than placebo for reading comprehension in children with symptomatic convergence insufficiency (CITT-ART, 2019). We work on the visual discomfort that gets in the way of schoolwork alongside — never instead of — reading instruction and classroom support.

Some visual complaints do settle on their own. In our offices, eye-teaming and focusing problems tend not to, and the near-work demand only grows as school does — which is why we would rather measure than wait. If several of the questions above sound like your child, a comprehensive developmental vision evaluation tests aiming, focusing and tracking directly. Schedule an evaluation at our Boynton Beach or Boca Raton office.