Metacognition in motion: The interplay between motor evidence and visual information in shaping sensorimotor confidence.

This study examines the role of internal motor signals and visual information in the detection of and confidence in Partial-errors (PEs), subtle endogenous motor corrections. Using electromyographic (EMG) recordings, we captured motor activations during a conflict task in which participants reported the presence of PEs and rated their confidence. Two experiments were conducted: Experiment 1 provided visible visual conflict through supraliminal primes, while Experiment 2 reduced visual feedback using subliminal primes. In both Experiments, participants demonstrated limited PE detection and above-chance metacognitive efficiency. Notably, when participants reported the absence of a PE, confidence was lower when a PE was actually present (unaware PE) compared to when there was no PE (correct rejection), suggesting implicit sensitivity to motor activation. Detection and confidence were systematically influenced by motor signals, with larger PE amplitudes and longer correction times leading to higher detection rates and confidence levels. However, a metacognitive bias emerged: confidence was paradoxically lower for detected PEs than for undetected ones, despite strong motor evidence. Visual information modulated the reliance on motor signals. In Experiment 2, where subliminal priming reduced visual feedback, motor signals had a more pronounced influence on both detection and confidence. These findings highlight the complementary roles of internal motor signals and external visual information in shaping sensorimotor confidence.