Force and timing variability in rhythmic unimanual tapping

Author(s): Dean, W. J., Newell, K. M.

Journal/Book: J Motor Behav. 2000; 32: 1319 Eighteenth St NW, Washington, DC 20036-1802, USA. Heldref Publications. 249-267.

Abstract: In 3 experiments the interdependencies between timing and force production in unimanual paced and self-paced rhythmic tapping tasks were examined as participants (N = 6 in each experiment) tapped (a) to 1 of 3 target periods (333 ms, 500 ms, and 1,000 ms), while they simultaneously produced a constant peak force (PF) over a 50-s trial; (b) to produce 1 of 3 target forces (5, 10, and 15 N) at their preferred frequency, while keeping their rhythm as invariant as possible; and (c) to all combinations of target force and period. The results showed that (a) magnitudes of force and period were largely independent; (b) variability in timing increased proportionally with tapping period, and the variability in force increased with peak force; (c) force variability decreased at faster tapping rates; and (d) timing variability decreased with increasing force levels. (e) Analysis of tap-to-tap variability revealed adjustments over sequences of taps and an acceleration in the tapping rate in unpaced conditions. The interdependencies of force and time are discussed with respect to the challenges they provide for an oscillator-based account.

Note: Article Sternad D, Penn State Univ, Dept Kinesiol, 266 Recreat Bldg, University Pk,PA 16802 USA

Keyword(s): force control; oscillator modeling; rhythmic timing; variability; MOTOR ACTS; TEMPORAL INTERVALS; STIMULUS SEQUENCE; ISOMETRIC TASKS; MOVEMENTS; MODEL; TIME; SYNCHRONIZATION; PERCEPTION; DYNAMICS

Zurück | Weiter