Final answer:
The accommodation mechanism enables the eye to focus on near objects by adjusting the lens’ focal length. Presbyopia can paralyze this mechanism, leading to difficulty in seeing near objects, and LASIK surgery for distance vision may still necessitate the use of reading glasses for close work.
Step-by-step explanation:
What can paralyze the accommodation mechanism, causing an inability to see near objects clearly? The accommodation mechanism of the eye involves adjusting its focal length for objects at different distances. In conditions such as presbyopia, this ability is impaired or lost, making close vision difficult. Presbyopia is often due to the natural aging process causing the lens to become less flexible. Other factors like certain medications, trauma, or diseases may also affect the accommodation mechanism.
A person with myopia, or nearsightedness, can see near objects clearly but has trouble with distant objects. Conversely, a person with hyperopia, or farsightedness, has difficulty with near vision. In both cases, corrective lenses are used to alter the eye's optical power to allow clear vision at all distances. Even after LASIK surgery to correct distant vision, individuals with presbyopia may still require reading glasses due to the inability of the eyes to accommodate or focus on close objects.