Final answer:
To gaze at the ceiling, your eyes perform a 'conjugate gaze,' a coordinated action where both eyes move in the same direction. This can include convergent or saccadic movements, depending on the object's distance and motion.
Step-by-step explanation:
The movement that allows you to gaze at the ceiling is known as conjugate gaze. This is a coordinated movement of the two eyes simultaneously in the same direction—to look upwards in this case. When your eyes move to focus on the ceiling or any object in a particular position, they engage in either convergent movements or saccadic eye movements. Convergence occurs when your eyes move to point at the same spot in space, a mechanism that is more engaged for closer objects. Saccadic movements are rapid, allowing the eyes to survey a complex visual stimulus or follow a moving object.