The Use of Iambic Pentameter in the

of the complete shape in the ambiguous prime emerged across time.
Visual search is another effective paradigm that can be used to test the time
course of object completion. Rauschenberger and Yantis (2001) used a visual search task
to test the organization of incomplete versus complete shapes across time. These
researchers showed that pre-shape completion information can affect performance in
short stimulus durations. To do this, these researchers disrupted the perceptual process at
different times. Participants were asked to search for a notched disk target in displays that
contained distracters that were comprised of paired complete disks and squares. In the
control condition, displays contained a notched disk target separated from a nearby
square. In the experimental condition, displays contained a notched disk target adjacent to
a square occluder. Rauschenberger & Yantis expected that search for the separate
notched disk target would be efficient, regardless of the number of distracter square disk
elements. If amodal completion was not accomplished in experimental conditions,
participants would perceive the notched disk and search for this disk should have been
efficient. In the adjacent condition however, after amodal completion, the nonadjacent
and notched disk would appear to be a full disk. Therefore, following completion, search
for the target in the adjacent condition might be inefficient because of its high degree of
similarity to the disk and square distracters. Each display was masked to limit exposure
time to 100ms or 250ms. These stimulus durations were selected because amodal
completion was thought to occur after 200ms of exposure (Sekuler & Palmer, 1992).
When displays were presented for 100ms, search for the notched disk target was efficient
in both experimental and control conditions. However, at 250ms stimulus durations,
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