High-gamma oscillations in the motor cortex during visuo-motor coordination: A tACS interferential study
E Santarnecchi1, A Biasella2, E Tatti2
1Department of Medicine, Surgery and Neuroscience, Neurology and Clinical Neurophysiology Section, Brain Investigation & Neuromodulation Lab. (Si-BIN Lab), University of Siena, Italy; Berenson-Allen Center for Non-Invasive Brain Stimulation, Beth Israel Medical Center, Harvard Medical School, Boston, MA, USA; Siena Robotics and Systems Lab. (SIRS-Lab), Engineering and Mathematics Department, University of Siena, Italy.
High-frequency gamma oscillations in the motor cortex enhance complex motor performance. This finding suggests potential therapeutic benefits for motor disorders involving impaired motor planning and execution.
Area of Science:
- Neuroscience
- Motor Control Physiology
- Human Motor Performance
Background:
- While beta, theta, and alpha oscillations are linked to motor control, gamma oscillations (40-90Hz) remain less understood.
- Gamma oscillations' role in motor physiology is crucial, with potential clinical relevance for motor disorders.
Purpose of the Study:
- To investigate the role of gamma oscillations in motor control using transcranial alternating current stimulation (tACS).
- To understand the chronometry of gamma activity during a visuo-motor coordination task.
Main Methods:
- Healthy volunteers performed a unimanual tracking task involving complex visuo-motor coordination.
- Transcranial alternating current stimulation (tACS) at 5Hz, 20Hz, 60Hz (mid-gamma), and 80Hz (high-gamma) or sham was applied to the motor cortex.
Main Results:
- High-gamma stimulation significantly enhanced motor performance.
- A trend for enhanced performance was observed with mid-gamma stimulation.
- These effects were most prominent 200-500ms after rapid changes in tracking trajectory.
Conclusions:
- High-frequency gamma oscillations in the motor cortex play a role in complex visuo-motor tasks requiring motor plan rearrangement.
- High-gamma stimulation may have a "prokinetic" effect, warranting investigation in motor disorders like Parkinson's disease.
