Differences in Mu rhythm when seeing grasping/motor actions in a real context versus on screens

Area of Science:

• Neuroscience
• Cognitive Science
• Human-Computer Interaction

Background:

• The Mu rhythm (8-12 Hz) in the somatosensory cortex is traditionally associated with motor actions and observation.
• The influence of the viewing medium (physical vs. screened) on this brain rhythm remains underexplored.

Purpose of the Study:

• To investigate how observing motor actions in different mediums (real-world performance vs. on-screen) affects the somatosensory Mu rhythm.
• To compare the neural response in the somatosensory cortex when viewing identical actions in distinct environments.

Main Methods:

• Electroencephalography (EEG) was used to record brain activity in 40 participants.
• Participants viewed identical narrative content presented as a live theatrical performance and a one-shot movie.
• Mu rhythm power in the left (C3) and right (C4) somatosensory areas was analyzed in response to 24 distinct motor actions.

Main Results:

• Lower Mu spectral power was observed in the somatosensory cortex after motor actions in the real performance condition compared to the on-screen condition.
• This reduction in Mu rhythm was more pronounced in the left hemisphere.
• Sensorimotor Mu rhythm event-related desynchronization (ERD) was significantly stronger during real-world observation than during screen observation.

Conclusions:

• The medium through which motor actions are perceived significantly modulates somatosensory cortex activity, specifically the Mu rhythm.
• Real-world observation elicits a stronger sensorimotor response than on-screen observation.
• Findings have implications for fields utilizing the somatosensory cortex, including online learning, virtual reality, and brain-computer interfaces.