Work

Mechanical load modulates premovement cortical activity during voluntary upper limb movement

Year: 2026

Type: article

Abstract: Examining how cortical activity changes under increasing motor demands may provide insights into how the brain prepares for movement. In this study, premovement cortical activity was examined with ten healthy male participants (n = 10) performing a unilateral bicep curl task. Cue-locked electroencephalography (EEG) signals preceding muscle activation were analyzed using event-related potentials, time–frequency decomposition, and cross-frequency coupling measures to characterize load-dependent cortical responses. As the load increased, premovement cortical responses showed temporal, frequency-specific, and spatially distributed patterns rather than uniform-amplitude scaling. These load-related differences were pronounced at higher load levels and exhibited non-monotonic and frequency-specific patterns across the frontal, central, and contralateral sensorimotor regions of the brain. These findings suggest that an increase in mechanical demand is associated with distinct task-dependent premovement cortical differences rather than linear scaling, showing band- and region-specific differences across conditions.

Source: Scientific Reports

DOI: 10.1038/s41598-026-72508-9