How background music rhythm modulates time perception: Evidence from the estimation of collision time.

Time-to-collision (TTC) estimation, the ability to predict when a moving object will reach a designated position, represents a critical skill for motor behavior regulation. However, although existing studies have demonstrated significant effects of object velocity and distance on TTC estimation, the role of auditory rhythm remains poorly understood. This study systematically investigated the influence of background musical rhythm on TTC estimation through two experiments (manipulating velocity and distance variables) combined with Bayesian modeling. The results demonstrated that ‌fast-tempo music enhanced the accuracy of visual TTC estimation under very low velocity and very near distance conditions. Additionally, a central tendency effect emerged across conditions, with extreme velocities or distances biasing estimates toward the mean. Bayesian modeling further uncovered distinct integration strategies - velocity processing relied on stabilized temporal priors, whereas distance judgments depended on reduced perceptual variability under fast-tempo conditions. These findings suggest that auditory rhythms influence visual TTC estimation by regulating attentional allocation and recalibrating internal timing mechanisms. The study advances our understanding of multisensory temporal perception and provides theoretical insights for practical applications like traffic safety management.