Researchers used functional magnetic（磁性的） resonance imaging (FMRI) to analyze brain activity in 20 people over age 60 by asking them to contemplate outdoor photos shown briefly.

    Then the elderly were presented with the picture of a face and asked to determine its gender and age, before being asked to recall details from the original scene they viewed.

    Researchers then compared their results to a similar experiment with 20 younger adults and found the brains of older subjects were less capable of disengaging from the interruption and reestablishing the neural connections necessary to switch back to focusing on the original memory.

    "Unlike younger individuals, older adults failed to both disengage from the interruption and re-establish functional connections associated with the disrupted memory network," write Wesley C. Clapp of the University of California, San Francisco, and colleagues in the Proceedings of the National Academy of Sciences.

    The study, published in the online edition of the journal Proceedings of the National Academy of Sciences, sheds new lights into a growing body of studies showing that one's ability to move from one task to another in quick succession becomes more difficult with age.(本文由在线英语听力室整理编辑)