Can Temporal Evolution of Simulated Tremor Burst Duration Provide an Electrophysiologic Perspective on Entrainment?
Handan Uzunçakmak-Uyanık, Fatma Gökçem Yıldız, Çağrı Mesut Temuçin
A
BSTRACT
Background:
Entrainment is a key feature in distinguishing between different tremor types but may be difficult to detect clinically. Electrophysiologic approaches, particularly electromyography (EMG)-based analyses, may provide objective insights. This study aimed to investigate whether burst duration of simulated tremors evolves over time under combined auditory–visual metronome guidance and to interpret this in the context of entrainment.
Materials and Methods:
Nineteen healthy right-handed volunteers performed 30-s tremor simulation tasks guided by a combined auditory–visual metronome (2 Hz). Surface EMG recordings were obtained, and burst durations were analyzed across early, middle, and late phases. Phase-dependent changes were assessed using the Friedman test. The linear mixed model (LMM) was used to evaluate time-dependent changes, and individual slope analyzes were performed to assess inter-individual variability (
Results:
Asignificant phase-dependent modulation of burst duration was observed (
Conclusion:
Simulated tremor burst duration does not evolve uniformly at the group level but reflects heterogeneous, individual-specific temporal dynamics. These findings suggest that entrainment may present as individualized sensorimotor adaptation rather than a group-level phenomenon. Burst duration evolution analysis may serve as a complementary electrophysiologic approach for assessing entrainment in addition to conventional coherence methods.