Effects of Visual and Auditory Feedback on the Mixed-Nerve Silent Period During Isometric Knee Extension Torque...

Sensory feedback plays an important role in isometric force regulation by modulating neural control during voluntary contraction. The mixed-nerve silent period (MnSP) is an electrophysiological index reflecting inhibitory neural mechanisms during voluntary muscle contraction. This study investigated the effects of visual and auditory feedback on MnSP during an isometric knee extension torque maintenance task in trained athletes. Twelve female collegiate basketball players performed a sustained knee extension torque task at 25% of maximal voluntary isometric contraction. The task was performed under two feedback conditions: visual feedback, in which participants adjusted torque by monitoring a real-time display, and auditory feedback, in which visual input was removed and torque was adjusted using standardized verbal instructions. MnSP was recorded from the ipsilateral opponens pollicis muscle following supramaximal median nerve stimulation. MnSP duration did not differ significantly between visual and auditory feedback in either the dominant or nondominant leg. Furthermore, no significant differences were observed between the dominant and nondominant legs within either feedback condition, although a moderate effect size was observed in the nondominant leg. These findings suggest that trained female basketball players exhibit similar MnSP responses under visual and auditory feedback during isometric force regulation.