The belief that voluntarily crossing one’s eyes can lead to them becoming permanently stuck is a common misconception. This notion often stems from childhood warnings. Understanding the biological mechanisms behind eye movement clarifies why this popular idea is not based on scientific reality.
How Your Eyes Move
The human eye moves through the coordinated effort of six external muscles, known as extraocular muscles. These muscles are attached to the outside of each eyeball and control all eye movements, including looking up, down, side to side, and rotating. Four are recti muscles (superior, inferior, medial, and lateral), and two are oblique muscles (superior and inferior).
These muscles operate in pairs, where one muscle contracts while its opposing muscle relaxes, allowing for smooth and precise eye movements. Crossing your eyes is a voluntary action, a natural function called convergence, which is essential for focusing on objects up close. The brain sends signals to these muscles to execute such movements. Once the voluntary command ceases, these muscles naturally relax and return the eyes to their normal, uncrossed alignment.
Understanding Strabismus
“Crossed eyes,” medically known as strabismus, is a condition where the eyes do not properly align when focusing on an object. This misalignment can cause one eye to turn inward (esotropia), outward (exotropia), upward (hypertropia), or downward (hypotropia). Unlike voluntary eye crossing, strabismus is a medical condition arising from various underlying issues.
The causes of strabismus are complex and do not include voluntarily crossing one’s eyes. It can result from problems with the neuromuscular control of eye movement, involving the brain or the eye muscles themselves. Other factors include muscle imbalances, nerve problems, or uncorrected vision issues like significant farsightedness.
Genetic predisposition also plays a role, with approximately 30% of children with strabismus having a family history. Certain medical conditions, such as cerebral palsy, Down syndrome, brain tumors, stroke, or head injuries, can also contribute.
While often appearing in childhood, strabismus can develop in adults. If left untreated, it can lead to complications like amblyopia (lazy eye) or double vision. Diagnosis and treatment by an eye care professional are necessary.
Dispelling the Myth: Is Crossing Your Eyes Harmful?
Voluntarily crossing your eyes cannot cause them to stay that way permanently. This idea is a common myth without scientific basis. The muscles controlling eye movement are robust and designed for flexible, temporary positions, always returning to their natural alignment once the voluntary action stops.
While prolonged voluntary eye crossing might lead to temporary eye strain or a mild headache, it does not cause any lasting damage to vision or permanently alter eye alignment. There is no scientific evidence to suggest that this common activity can induce strabismus. Therefore, voluntarily crossing your eyes is generally harmless to your eye health.