Question

read the passage.
camera - like memory
do some individuals have the amazing ability to take perfectly accurate, permanent mental \snapshots,\ which can be stored in the brain for future retrieval? fictional figures aside, no. but while this popular notion of \photographic memory\ is unfounded, research has demonstrated the existence of a fascinating phenomenon called eidetic memory, in which memory actually does have a camera - like quality. people with eidetic memory are able to look at an object or picture and then look away or close their eyes and continue to \see\ the object or picture in their minds. these images last only a few minutes at most before dissipating, and they are typically not entirely accurate. still, the degree of detail that \eidetikers\ can recall during those first few minutes is astonishing. interestingly, the phenomenon occurs almost entirely in children, with an estimated two to ten percent of children affected; virtually all eidetikers lose their unusual ability before reaching adulthood.
what is the main, or central, idea of the passage?
nearly all individuals with eidetic memory are children.
individuals with eidetic memory are temporarily able to retain detailed images in their minds.
an eidetic memory can occur after a person closes his or her eyes or looks away from an object.

Explanation:

The passage mainly discusses eidetic memory. It describes how people with eidetic memory can "see" an object or picture in their minds after looking away, and that these images are detailed but temporary, lasting only a few minutes. While it mentions that most eidetikers are children, this is not the main idea. The key is the ability to temporarily retain detailed mental images.

Answer:

Individuals with eidetic memory are temporarily able to retain detailed images in their minds.