Regulating tempo in a continuation finger-tapping task
It is well known that people can produce rhythms, such as finger tapping, but what is not well known is how such rhythms are maintained. One way to measure rhythm is through “continuation finger-tapping,” in which subjects are asked to tap along with audible tones and then maintain that rate after the tones stop. ^ The purpose of this study was to determine whether there was evidence of two strategies for regulating rhythms: (1) Subrange/tapping style, and (2) Targeted drift-and-correction. Both archival and new data were analyzed for this research. ^ The first goal was to determine whether two subranges of tapping exist, and whether subjects used different strategies for each subrange as reported in Vaughan, Matson, & Rosenbaum (1998). Two different variables were analyzed for the subrange/tapping style phase of the study: Duty Cycle (normalized time-on-target) and Velocity (force upon target). ^ The second goal was to determine whether subjects used a “target-sweeping” strategy, wherein they introduced small negative biases (“drift”) which would then be countered by larger positive corrections. If this method were used to maintain a steady average rate, the distributions of tap interval First Differences would show evidence of bimodal symmetry. ^ The subranges finding is that Duty Cycle and Velocity change continuously as a function of ISI. This finding stands in contrast to two hypotheses that were previously plausible: (1) Duty cycle could have been constant, which would suggest that finger-tapping is a simple process in which its motor elements are proportionately scaled to match a particular tempo. Instead, the data suggest that the motor components change independently over target rate; (2) Proposed subrange boundaries could have been differentiated by discontinuous change; however, the data suggest that there is a gradual, rather than an abrupt transition over target tapping rates. ^ The drift/corrections finding; is that distributions of IRI First-Differences do not conform to the prediction of a simple drift-and-correction theory of tempo regulation. Instead of a bimodal distribution, with one component representing numerous little “drifts” and the other representing a few bigger “corrections”, we see a variety of distributional shapes, most of which are unimodal. ^
Arthur Allen Little,
"Regulating tempo in a continuation finger-tapping task"
Dissertations and Master's Theses (Campus Access).