"They would know there should be a sea, that there would be sand, but in the way they described it, they'd say, I just can't visualize the whole scene as you'd like," she added.
Without an environment or location to house a scene, amnesiacs may be unable to recreate or imagine normal experiences.
"If you think about memories, they are always somewhere, because things happen somewhere," Maguire explained. "So spatial context is very important for our experiences."
Placing a Memory
Scientists believe that the brain recalls past events by meticulously reconstructing the individual cues of an experience—the people, objects, and other aspects that composed the scene.
This process is thought to occur in a region of the brain known as the hippocampus, which was damaged in the amnesiac patients studied. (Related: "First Ever Brain 'Atlas' Completed" [September 26, 2006].)
The new study implies that similar processes in the hippocampus are also used to imagine future events, suggesting that memory and imagination are two sides of the same coin.
The hippocampus may provide the spatial context that binds and blends the people, objects, and other aspects of a memory—or an imagined event.
"Maybe the hippocampus," Maguire said, "is the basic scaffold around which memories are hung."
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