The Use of Iambic Pentameter in the

information.
Stimuli presented during the practice trials were unambiguous as to interpretation,
either by coarse or fine spatial scale, thus familiarizing participants with one type of scale
interpretation task. Immediately after the practice trials, participants were asked to
perform the same task with ambiguous coarse/fine stimuli. If scale selection were based
on task demands, participants who practiced identifying coarse scene details in the
unambiguous practice stimuli would likely perceive the coarse scenes in the ambiguous
experimental stimuli. Likewise, participants who practiced identifying fine scene scales
in the unambiguous practice stimuli would perceive the fine scenes in the ambiguous
experimental stimuli. Indeed this was the case. In short stimulus durations, participants
were selecting scales to perceptually organize based on task demands. In effect,
perceptual organization was dependent upon what scale of information needed to be
processed first, based on the task. The results of both experiments by Oliva and Schyns
(1997) support the Flexible Usage hypothesis.
The Fixed and Flexible Usage hypotheses are each interesting interpretations of
visual processing by spatial scale. While it is not clear which of these two hypotheses is
correct, what is clear is that low and high spatial frequency scales are used in a temporal
sequence in visual processing.
Object completion. While some researchers chose to study the time course of
perceptual organization in terms of coarse and fine or global and local scene properties,
others chose to look at this problem in terms of object completion. For example, Sekuler
and Palmer (1992) used matched priming to determine whether participants perceived an
42