Electrophysiological correlates of tactile and visual perception during goal-directed movement

Tactile information arriving at our sensory receptors is differentially processed over the various temporal phases of goal-directed movements. By using event-related potentials (ERPs), we investigated the neuronal correlates of tactile information processing during movement. Participants performed goal-directed reaches for an object placed centrally on the table in front of them. Tactile and visual stimuli were presented in separate trials during the different phases of the movement (i.e., preparation, execution, and post-movement). These stimuli were independently delivered to either the moving or the resting hand. In a control condition, the participants only performed the movement, while omission (movement-only) ERPs were recorded. Participants were told to ignore the presence or absence of any sensory events and solely concentrate on the execution of the movement. The results highlighted enhanced ERPs between 80 and 200 ms after tactile stimulation, and between 100 and 250 ms after visual stimulation. These modulations were greatest over the execution phase of the goal-directed movement, they were effector-based (i.e., significantly more negative for stimuli presented at the moving hand), and modality-independent (i.e., similar ERP enhancements were observed for both tactile and visual stimuli). The enhanced processing of sensory information over the execution phase of the movement suggests that incoming sensory information may be used for a potential adjustment of the current motor plan. Moreover, these results indicate a tight interaction between attentional mechanisms and the sensorimotor system.