Instantaneous Beta Frequency Regulates Self-Generated Timing in Humans

Abstract

Self-generated timing requires the brain to determine when to terminate an ongoing action without reference to external cues. Although beta-band oscillations have been implicated in temporal control, how their intrinsic dynamics shape moment-to-moment variability in internally generated time remains unclear. Here, combining scalp EEG with intracranial recordings in humans, we show that the instantaneous frequency of beta oscillations (13-30 Hz) provides a dynamic control signal for self-generated timing. During a self-paced time production task, higher instantaneous beta frequency reliably predicted longer produced durations, both within individuals on a trial-by-trial basis and across individuals. This relationship was beta-specific, frontoparietally distributed, robust to motor and spectral confounds, and validated by convergent intracranial recordings. These findings run counter to classical pacemaker-accumulator models and instead establish beta-frequency dynamics as a mechanism that delays action termination by increasing the density of intrinsic stabilizing control updates during self-generated timing.