Registered Practical Nurse (RPN) Practice Test

What causes impaired adaptation to darkness in older adults?

1. Genetic predisposition

2. Structural changes to the eye

3. Chronic health conditions

4. Lack of exposure to light

The correct answer is: Structural changes to the eye

Impaired adaptation to darkness in older adults is primarily caused by structural changes to the eye. As individuals age, several physiological changes occur in the eye that can impact vision, particularly in low-light conditions. One of the key structural changes is the gradual decline in the number of rod cells in the retina, which are responsible for night vision and adapting to low-light environments. Additionally, the lens of the eye may become more opaque due to cataract development, contributing to difficulties in seeing in dim lighting. These changes can result in slower adjustment times to darkness, making it challenging for older adults to navigate environments with varying light levels. While genetic predispositions and chronic health conditions can influence vision, and lack of exposure to light can impact visual health, the primary issue affecting the adaptation to darkness specifically in older adults is the physiological and structural changes that occur within the eye itself.