your attention, independent of your local goals as a perceiver. Research sug-
gests, for example, that new objects in a perceptual display automatically cap-
ture attention.
Consider the figure shown in part A of figure 7.9. How hard do you think
it would be for you to identify the overall, global figure as an H? The an-
swerwilldependontheextenttowhichyouhavetoattendtothelocal
letters that make up the global figure. Parts B and C of the figure show
how researchers manipulated attention. In each condition of the experi-
ment, subjects were given a preview display that consisted of a figure 8
made of 8s. In the control condition, the figure 8 was complete. But, as
you can see, in the novel object condition, there was a gap in the figure.
What will happen if the next display you see fills in that gap? The
researchers predicted that the object filling the gap (the novel object)
would capture your attention—you couldn’t help looking at it. And if
your attention is focused on the letter S, you should find it harder than
you ordinarily would to say that the global letter is an H.
That is exactly the result the researchers obtained. If you compare the
two test displays in figure 7.9, you’ll see that they are identical. In each
case an S helps to make up the global H. However, it was only in the caseFigure 7.9
Stimulus-driven capture. How hard is it to recognize that the figure in (A) is an H? When the S fills
a prior gap in the display (C), subjects find it more difficult to see that the overall figure is an H than
they do in the control condition (B).
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