Tapping with intentional drift.

Area of Science:

• Human motor control
• Auditory-motor synchronization
• Timing and rhythm perception

Background:

• Rhythmic tapping studies often aim to minimize frequency drift.
• The Wing and Kristofferson model explains tapping timing via a clock and motor delays.
• Understanding drift's impact on timing models is crucial.

Purpose of the Study:

• Compare constant frequency tapping with intentional frequency drift (decreasing ITI).
• Investigate how tapping frequency influences motor output and timing parameters.
• Assess the applicability of the Wing and Kristofferson model to non-constant tapping.

Main Methods:

• Synchronization-continuation paradigm for tapping tasks.
• Recorded tapping forces and index finger electromyograms (EMG).
• Derived inter-tap intervals (ITIs), variability, and Wing and Kristofferson model parameters (clock and motor variances).

Main Results:

• Increasing frequency (decreasing ITI) led to greater deviation from intended ITIs.
• Tapping frequency generally affected force, variability, model parameters, and muscle co-activation.
• Timing parameters for decreasing ITI tapping were comparable to constant frequency tapping.

Conclusions:

• Intentional frequency drift in tapping is more difficult but shares timing properties with constant tapping.
• The Wing and Kristofferson model effectively describes timing in both constant and drifting tapping sequences.
• Motor control and timing mechanisms remain consistent despite intentional frequency changes.