For other uses, see Non-fiction (disambiguation). Non-fiction or nonfiction is content (sometimes, in the form of a story) whose creator, in good faith, assumes responsibility for the truth or accuracy of the events, people, and/or information presented. In contrast, a story whose creator explicitly leaves open if and how the work refers to reality is usually classified as fiction.
For each eye, six muscles work together to control eye position and movement. Two extraocular muscles, the medial rectus and lateral rectus, work together to control horizontal eye movements (Figure 8.1, left). 1  Contraction of the medial rectus pulls the eye towards the nose (adduction or medial movement).
The primary muscle that moves an eye in a given direction is known as the agonist. A muscle in the same eye that moves the eye in the same direction as the agonist is known as the synergist, while a muscle in the same eye that moves the eye in the opposite direction of the agonist is the antagonist.