American Board of Ophthalmology (ABO) Practice Exam

Which of the following is NOT one of the muscle actions involved when reading?

1. Pupil constriction

2. Eye convergence

3. Lens accommodation

4. Eye rotation

The correct answer is: Eye rotation

The action of eye rotation is not specifically involved in the process of reading. When reading, the primary motor activities of the eye include pupil constriction, eye convergence, and lens accommodation. Pupil constriction occurs to optimize the depth of field and improve clarity of vision for near tasks like reading. Eye convergence is necessary as the eyes turn inward to maintain single, clear vision of nearby objects. Lens accommodation allows the eye to change its focus from distant to near objects, adjusting the curvature of the lens to ensure the text is sharp and clear. In contrast, eye rotation is a more general term that describes the movement of the eyes in various directions but does not specifically facilitate the reading process like the other actions mentioned. Therefore, while eye rotation can occur in various visual tasks, it is not a necessary action associated with reading itself.