| Abstract | Continuous circle drawing is considered a paragon of emergent
timing, whereas the timing of finger tapping is said to be eventbased.
Synchronization with a metronome, however, must to some
extent be event-based for both types of movement. Because the
target events in the movement trajectory are more poorly defined
in circle drawing than in tapping, circle drawing shows more variable
asynchronies with a metronome than does tapping. One factor
that may have contributed to high variability in past studies is
that circle size, drawing direction, and target point were prescribed
and perhaps outside the comfort range. In the present study, participants
were free to choose most comfortable settings of these
parameters for two continuously drawn shapes, circles and infinity
signs, while synchronizing with a regular or intermittently perturbed
metronome at four different tempi. Results showed that
preferred circle sizes were generally smaller than in previous studies
but tended to increase as tempo decreased. Synchronization
results were similar for circles and infinity signs, and similar to
earlier results for circles drawn within a fixed template (Repp &
Steinman, 2010). Comparison with tapping data still showed
drawing to exhibit much greater variability and persistence of
asynchronies as well as slower phase correction in response to
phase shifts in the metronome. With comfort level ruled out as a
factor, these differences can now be attributed more confidently
to differences in event definition and/or movement dynamics. |