During the 1960s, researchers at Cornell University conducted a series
    of tests on the effects of working with music. They polled a group of
    computer science students and divided the students into two groups, those
    who liked to have music in the background while they worked (studied) and
    those who did not. Then they put half of each group together in a silent
    room, and the other half of each group in a different room equipped with
    earphones and a musical selection. Participants in both rooms were given
    a Fortran programming problem to work out from specification. To no
    one's surprise, participants in the two rooms performed about the same
    in speed and accuracy of programming. As any kid who does his arithmetic
    homework with the music on knows, the part of the brain required for
    arithmetic and related logic is unbothered by music—there's another
    brain center that listens to the music.

    The Cornell experiment, however, contained a hidden wild card. The
    specification required that an output data stream be formed through a
    series of manipulations on numbers in the input data stream. For example,
    participants had to shift each number two digits to the left and then
    divide by one hundred and so on, perhaps completing a dozen operations
    in total. Although the specification never said it, the net effect of
    all the operations was that each output number was necessarily equal to
    its input number. Some people realized this and others did not. Of those
    who figured it out, the overwhelming majority came from the quiet room.