øyemuskulaturen

The eye musculature refers to the collection of muscles that control the movement of the eyeball and the shape of the lens. These muscles are crucial for vision, enabling us to focus on objects at different distances and to direct our gaze. There are two main groups of muscles associated with the eye: the extrinsic muscles and the intrinsic muscles.

The extrinsic eye muscles are responsible for the gross movements of the eyeball. There are six extrinsic muscles for each eye: four rectus muscles (superior, inferior, medial, and lateral) and two oblique muscles (superior and inferior). These muscles attach to the outer surface of the eyeball and the bones of the orbit, allowing for movements such as looking up, down, left, right, and in a rotational manner. Their coordinated action is essential for binocular vision, ensuring that both eyes focus on the same point.

The intrinsic eye muscles are located within the eyeball itself and control finer adjustments. The iris contains the sphincter pupillae and dilator pupillae muscles, which regulate the size of the pupil. This adjustment controls the amount of light entering the eye, similar to how the aperture of a camera works. The ciliary muscle is responsible for changing the shape of the lens, a process called accommodation. By altering the lens's curvature, the eye can focus light from objects at varying distances onto the retina, enabling clear vision whether looking at something close or far away. All of these muscles are controlled by specific cranial nerves, ensuring precise and rapid responses to visual stimuli.