What is adaptation in the context of vision?

Adaptation in the context of vision specifically refers to the process by which our eyes adjust to varying levels of light. This adjustment allows us to see clearly in different lighting conditions, such as transitioning from bright sunlight to a dimly lit room.

When light levels change, the photoreceptors in our eyes—cones and rods—respond accordingly. In bright light, the pupils constrict to limit the amount of light entering the eye, protecting the retina from potential damage and enhancing contrast. Conversely, in low light, the pupils dilate to maximize light intake, allowing the rods to become more active for night vision. This remarkable ability to adapt ensures we maintain visual acuity across a wide range of environments.

Other options do not accurately capture the concept of adaptation in vision. Increasing brightness, seeing without light, and adjusting eye color do not relate to the eye's ability to adjust to changing lighting conditions.