The duration that the human eye can retain a visual image is called what?

The concept you are looking for is known as integration, which refers to the duration that the human eye can retain a visual image. In the context of human vision, integration is essential for understanding how we perceive motion and continuity. When light enters the eye, it creates a temporary image on the retina, which can be held for a brief period even after the stimulus has changed or is no longer present. This ability to retain an image helps our brain process visual information more efficiently and helps create a seamless perception of the visual world.

While other terms are relevant to vision, they describe different aspects of visual function. Adaptation involves the eye's adjustment to different light levels; acuity refers to the clarity or sharpness of vision; and illumination relates to the level of light available for seeing. Integration specifically addresses how visual information is retained and processed over time, making it the correct choice for your question.