Impact of sensory integration in modulating neuronal oscillation bands and antagonist vibratory response during co-vibration.

INTRODUCTION: Kinesthetic illusion (KI) induced by tendon vibration (VIB) is known for activation in sensorimotor areas and antagonist vibratory response (AVR) of the antagonist muscle. We hypothesize that coupling between cortical activation and corresponding AVR activity occurs during KI induced by VIB. This study aimed to explore the neurophysiological features of KI induced by VIB associated with brain activity and muscle activity. METHODS: Two experimental sets, without-hand-cover (wo) and with-hand-cover (w), included three co-vibration frequency patterns applied to the flexor carpi radialis and extensor carpi radialis muscles: 80:80 Hz, 115:45 Hz, and 70:0 Hz, resulting in six conditions. RESULTS: AVR-electromyography (EMG) activity differed significantly between w-70:0 vs. wo-70:0 and between w-70:0 vs. w-80:80 (adjusted p < 0.05). Event-related desynchronization (ERD) of electroencephalography did not differ significantly between conditions. KI strength was significantly higher in both w-115:45 and w-70:0 conditions than in w-80:80 conditions (adjusted p < 0.01). Spearman's correlation for w-conditions (w-115:45 and w-70:0) revealed a significant correlation between both α-and γ-ERD at C3 with AVR-EMG activity (ρ = 0.37, p < 0.05) and a significant negative correlation between γ-ERD with KI at CP3 (ρ = -0.36, p = 0.049) and P3 (ρ = -0.40, p = 0.027). No similar correlation was observed for wo-conditions. DISCUSSION: These significant correlations emerged under distinct KI conditions, suggesting condition-and region-specific cortical engagement.