Quantifying phase correction in sensorimotor synchronization: empirical comparison of three paradigms.

Area of Science:

• Auditory Neuroscience
• Motor Control
• Human Sensorimotor Synchronization

Background:

• Phase error correction in sensorimotor synchronization is often modeled using a single-parameter autoregressive model.
• The parameter α quantifies sensorimotor coupling strength, reflecting the degree of influence between motor output and sensory feedback.

Purpose of the Study:

• To compare sensorimotor coupling strength (α) estimates derived from three distinct metronome paradigms: regular (RM), phase-shifted (PS), and adaptively timed (AT).
• To investigate how different metronome perturbation types influence phase correction mechanisms during synchronous tapping.

Main Methods:

• Musically trained participants performed tapping synchronization tasks under RM, PS, and AT conditions across four tempi (400–1300 ms intervals).
• Two distinct estimation methods were applied to analyze sensorimotor coupling strength (α) from the collected tapping data.

Main Results:

• Sensorimotor coupling strength (α) estimates increased with interval duration across all paradigms.
• The phase-shifted (PS) metronome paradigm yielded significantly higher α values than the adaptively timed (AT) paradigm, with regular metronome (RM) values falling in between.
• PS α estimates were uncorrelated with RM and AT estimates, while RM and AT estimates were strongly correlated.

Conclusions:

• Abruptly perturbed metronome sequences (PS) appear to engage different phase correction mechanisms than regular (RM) or continuously modulated (AT) sequences.
• The findings suggest distinct neural processes underlie sensorimotor adaptation to predictable versus unpredictable timing perturbations.