Why does night driving become especially difficult in late adulthood?
because of diminishing sensitivity to contrasts and reduced tolerance for glare
because of the decline in color vision
because of declines in sustained attention
because of the expanding area of the visual field
The Correct Answer and Explanation is:
The correct answer is:
because of diminishing sensitivity to contrasts and reduced tolerance for glare
Explanation:
Night driving becomes especially difficult in late adulthood primarily due to changes in the eyes and visual processing associated with aging. Two key factors contribute significantly: diminished sensitivity to contrasts and reduced tolerance for glare.
- Diminished Sensitivity to Contrast:
As people age, the ability to distinguish between objects and their backgrounds, especially in low-light conditions, declines. This diminished contrast sensitivity makes it harder for older adults to see subtle differences in shades and shapes on the road at night. For example, it becomes more difficult to detect pedestrians, road signs, or obstacles that don’t stand out sharply against their surroundings. The aging eye’s lens may also become denser and more yellow, further reducing the transmission of light and decreasing contrast perception. - Reduced Tolerance for Glare:
Glare from oncoming headlights or streetlights is more disturbing for older adults because of changes in the eye’s lens and pupil. The aging lens tends to scatter more light, and the pupils often become smaller and less responsive, limiting the eye’s ability to adjust quickly to changes in brightness. This increased glare sensitivity causes temporary blindness or visual discomfort when exposed to bright lights, such as headlights at night, making driving much harder and more dangerous.
Other factors listed in the question are less relevant or incorrect in explaining the difficulty of night driving in late adulthood:
- Decline in Color Vision: While aging can affect color vision, it is less significant for night driving because the ability to see in low light relies more on rods (which do not detect color) than cones (which do). Color vision declines generally do not majorly impact night driving.
- Declines in Sustained Attention: Although cognitive factors like attention may decline with age and affect driving safety overall, they are not the primary reason night driving is more difficult.
- Expanding Area of the Visual Field: Visual field typically narrows, not expands, with age, so this option is inaccurate.
In summary, the most critical physiological reasons for increased difficulty in night driving among older adults are diminished contrast sensitivity and reduced tolerance for glare, which affect the ability to see clearly and comfortably in low-light conditions.