Enhanced corticomuscular coherence by external stochastic noise.

Area of Science:

• Neuroscience
• Human Performance

Background:

• Stochastic resonance (SR) is a phenomenon where adding optimal noise (ON) can improve system performance.
• SR is being explored to enhance human capabilities.

Purpose of the Study:

• To investigate if performance improvements from ON in a visuomotor task correlate with increased cortical motor spectral power (SP) and corticomuscular coherence.
• To explore the neural mechanisms underlying SR-induced performance enhancement.

Main Methods:

• Eight subjects performed a visuomotor task, compensating for static force with their index finger.
• Electroencephalogram (EEG) from the motor cortex, electromyogram (EMG) from muscles, and finger position were recorded.
• Performance was quantified using mean absolute deviation (MAD).

Main Results:

• Optimal noise (ON) significantly improved motor accuracy (reduced MAD) compared to zero noise.
• Cortical motor SP and corticomuscular coherence in the beta-range were enhanced under ON conditions.
• These neural changes correlated with the observed performance improvements.

Conclusions:

• The findings support the hypothesis that SR enhances sensorimotor performance through increased cortical motor SP and corticomuscular coherence.
• This study provides evidence for the neural basis of performance enhancement via stochastic resonance.