Can Classroom Design Affect Myopia Progression?

HOT TOPIC

Link Between Respiration and Pupil Changes, Study Finds

A recent study in The Journal of Physiology has uncovered a fascinating link between breathing and pupil size, offering insights that may intrigue eye care professionals. The research demonstrates that pupil diameter fluctuates with the respiratory cycle, reaching its smallest size during inhalation and its largest during exhalation. This rhythmic variation, observed in light- and dark-adapted conditions, suggests a fundamental physiological mechanism connecting respiratory phases to visual processing. For ophthalmologists and optometrists, this finding could have implications for understanding how autonomic functions influence eye behavior beyond traditional light-driven responses.

The study involved 40 healthy young adults whose pupil sizes were meticulously tracked using high-resolution eye-tracking technology while their breathing was monitored via nasal airflow sensors. The results revealed a consistent pattern: pupil constriction aligns with inhalation, while dilation peaks during exhalation, with an average size difference of about 0.05 mm—small but statistically significant. This oscillation persisted regardless of whether participants breathed naturally or followed a metronome, indicating a robust, involuntary link. Intriguingly, the effect diminished when participants held their breath, pointing to active respiration as the driver.

For eye doctors, this discovery raises questions about how respiratory-driven pupil changes might affect visual acuity or diagnostic assessments, such as pupillary light reflex tests. The researchers propose that this phenomenon could stem from shared neural pathways in the brain stem, where respiratory and pupillary control centers overlap, or from mechanical influences of breathing on intracranial pressure. While the study doesn’t directly address clinical applications, it opens the door to exploring whether conditions such as sleep apnea or chronic respiratory diseases—both of which an optometrist is no stranger to—might subtly alter pupil dynamics. This could prompt future research into refining diagnostic tools or understanding visual perception variations linked to breathing patterns, enriching the intersection of ophthalmology and systemic physiology. (Read more here.)

My Two Cents

This is a fascinating take on a test that many of us take for granted, except for the queen of neuro-optometry herself, Jacqueline Theis, OD, FAAO, FNAP, who has been beating the drum of just how valuable pupillary testing is for quite some time now. Practitioners like Dr. Theis have been preaching how much the pupils can tell us, and including some recent studies that show they can be used to diagnose neurological conditions such as Parkinson disease, where damage to pupil function is accepted as an early sign of the disease.

OUTSIDE THE LANE

New Research Shows Simulated Time Outside Can Slow Myopia Progression

An article from New Scientist reported on a study from the Guangzhou Women and Children’s Medical Center in China showing that classrooms designed to resemble woodlands might slow myopia progression in children. The 2-year trial involved more than 1,700 first graders across six Chinese schools, with half the schools featuring forest-themed décor (ie, tree-patterned wallpaper, plants, and natural motifs). Results showed a lower incidence of myopia (18.7%) in the intervention group versus the control group (26.8%), suggesting a protective effect. This hints at a novel environmental influence on refractive development beyond the known benefits of outdoor time.

Weizhong Lan/AIER Academy of Ophthalmology, Central South University

The study leverages the established connection between natural settings and reduced myopia risk, typically tied to light exposure and distant focus. Here, the woodland decor alone—without changes in lighting or outdoor schedules—appeared to make a difference in the incidence of myopia. Researchers speculate that green tones and natural patterns might ease visual strain or subtly alter focus habits, although the mechanisms are unconfirmed. Eye doctors might consider this an adjunct to myopia control methods such as orthokeratology or atropine, especially when outdoor access is limited.

Although the study findings are compelling, the study itself lacks axial length data and long-term follow-up, tempering clinical implications. Still, it highlights the myopia crisis, which is projected to affect half the globe by 2050, and it invites eye care professionals to consider how classroom design could support vision health. This could spark further research or collaborations with educators, offering a fresh perspective on managing this growing public health challenge.

My Two Cents

Woah! This is something to take note of and is one of the more interesting studies I’ve seen recently. I can’t speak to the study's validity, and it definitely requires a bit more follow-up, but what a fascinating concept! Here’s hoping further studies on this concept are in the works!

CAN YOU RELATE

The Dunning-Kruger effect is a cognitive bias and describes the tendency of individuals with limited knowledge or skills in a specific area to overestimate their competence. At the same time, those who are subject matter experts may underestimate their abilities.

Recently, someone I admire tremendously, Cecelia Koetting, OD, FAAO, Dipl ABO, interviewed me on The MOD Pod. Dr. Koetting made a few remarks about my knowledge and expertise on dry eye and other areas of eye care. She paid me compliments, and I immediately shied away from them—after all, I’m just an average OD in an average college town seeing an above-average amount of patients. Dr. Koetting is royalty in this profession and one of the queens of eye care education. Who am I to be considered an expert on anything, let alone by her? Days later, I received a few more compliments from other giants in the eye care profession. It immediately made me feel undeserving and like a total fraud. After all, I get incredibly awkward when anyone compliments me, and I freeze up before blurting something out that doesn’t make sense. It’s the nerd curse.

This whole situation got me thinking: Why am I like this? Why do I feel more uncomfortable in my own skin recently when treating dry eye and other ocular issues despite my knowledge base increasing substantially over the past few years? Why do I feel like a fraud because my decision tree is ever-evolving? Is it the sheer number of treatment options that are now available, or is it more of a mental thing?

According to my therapist, it’s likely the Dunning-Kruger effect. As I’ve learned more and more about dry eye and other ocular disease processes, I’ve become less confident in creating treatment algorithms, which seems counter-intuitive from someone who is labeled an expert in an area. After discussing my little psych issue with many of my most esteemed colleagues, it seems I’m not the only one who feels this way.

As we continue to learn more about our specialty and the human eye, it seems natural for us to become less familiar with our treatments and decisions. So, if you’re like me and feel like you’re second-guessing yourself more lately, take comfort in the fact that it could very well be because you’re more knowledgeable about your field than you’ve ever been before and that second-guessing is actually due to all of the new and ever-changing knowledge you are encountering.