Understanding Tired Eyes - Know the Different Eye Muscles
In order to understand eye strain better, it is important to learn more about the muscles of the eye first. There are actually six skeletal muscles around the eye, and they control the different movements that the eyes make.
While the muscles of the eyes are small and not that strong, they are precise and fast. The muscles allow your eyes to do various complicated tasks that include scanning for objects, maintaining a stable image on the retina, and tracking moving objects. When you have tired eyes, the muscles act more sluggish. That’s why you have a hard time focusing or looking for objects.
The six skeletal eye muscles are medial rectus, lateral rectus, inferior rectus, superior rectus, inferior oblique, and superior oblique.
Anatomy of the Eye Muscles
The six muscles around the eyes work against each other in order to make the eyes move. Excluding the inferior oblique, all the eye muscles are attached to a tendinous band around the optic nerve to form a cone. The band is called annulus of Zinn, which serves as an anchor to the eye muscles to the posterior of the orbit. They also provide holes for the optic nerves to enter the orbit.
Eye Muscle Movements
When there is no eye strain, the eye muscles work with the other muscles to move both eyes to the same direction. Below are how the individual eye muscles work to control movement.
Medial rectus moves the eye to go towards the nose. To move the eye to the opposite direction or away from the nose, you use the lateral rectus.
The superior rectus makes the eyes move at an upward motion, and rotate the top part of the eye to go toward the nose. The inferior rectus does the opposite. It makes the eye move downward, and rotate it away from the nose. Both the superior rectus and inferior rectus muscles make the eye move inward.
The superior oblique rotates the top of the eyes to the nose, and move it downward. The inferior oblique rotates the top of the eye outward from the nose, and upward. Both superior oblique and inferior oblique muscles move the eye outward.
The main muscle that controls the eye movements is known as the agonist. A muscle found in the same eye and makes the eye move with the direction as that of the agonist is called the synergist. The muscle that moves it in the different direction is an antagonist.
The muscles of the eye are responsible for the rotation and movement of the eye. They are also used in tracking moving objects and adjusting the position of the eye to create a binocular image. Tired eyes often lead to blurred or double vision, which can result to different images presented to the brain. That’s why it is important treat eye strain right away.