Related Experiment Video
Updated: May 18, 2026
12:33
Corticospinal Excitability Modulation During Action Observation
Published on: December 31, 2013
It is not all about phase: amplitude dynamics in corticomuscular interactions
Zubeyir Bayraktaroglu1, Katherina von Carlowitz-Ghori, Gabriel Curio
1Neurophysics Group, Department of Neurology, Charité - Universitätmedizin, Campus Benjamin Franklin, 12203, Berlin, Germany.
Neuroimage
|September 11, 2012
Summary
This study reveals that the amplitude of brain beta oscillations influences muscle activity communication. Beta oscillation amplitude dynamics, not just phase, are transmitted from the brain to muscles via the spinal cord.
Area of Science:
- Neuroscience
- Motor Control
- Biomedical Engineering
Background:
- Corticomuscular coherence (CMC) using EEG/EMG is standard for studying brain-muscle interactions.
- Existing methods lack the ability to quantify amplitude dynamics of sensorimotor oscillations.
Purpose of the Study:
- To investigate the amplitude dynamics of sensorimotor EEG beta oscillations during isometric tasks.
- To explore the relationship between these amplitude dynamics and corticomuscular coherence (CMC).
Main Methods:
- Utilized multichannel EEG and EMG recordings to derive amplitude envelopes of beta oscillations.
- Analyzed signal-to-noise ratio of pre-stimulus beta oscillations.
- Assessed the correlation between beta oscillation attenuation and CMC strength.
Main Results:
- Cortical beta oscillation amplitude influences CMC through signal-to-noise ratio and stimulus-induced attenuation.
- Attenuation of beta oscillations upon stimulus correlates with CMC strength, suggesting increased cortical excitability.
- Positive correlations found between EEG and EMG beta oscillation amplitude envelopes (50-1000 ms), indicating transmission of amplitude dynamics.
Conclusions:
- Cortical beta oscillations transmit both phase and amplitude dynamics to spinal motoneurons and peripheral effectors.
- Amplitude dynamics provide a complementary measure to CMC for understanding corticomuscular interactions.
- Amplitude-envelope correlations may be more sensitive to signal-to-noise ratio than CMC.
Related Concept Videos
01:20Excitation-Contraction Coupling in Skeletal Muscles
Excitation-contraction coupling is a series of events that occur between generating an action potential and initiating a muscle contraction. It occurs at the triad, a structure found in skeletal muscle fibers that comprise a T-tubule and terminal cisternae of the sarcoplasmic reticulum on each side. These triads are visible in longitudinally sectioned muscle fibers. They are typically located at the A-I junction — the junction between the A and I bands of the sarcomere.
When an action potential...
When an action potential...
01:20Motor Unit Stimulation
When the neuron of a motor unit fires an action potential, it triggers a series of events, leading to a twitch contraction in the muscle fibers. The process of excitation-contraction coupling is crucial in relaying the action potential to the muscle fibers.
The latent period of contraction marks the onset of excitation-contraction coupling, when the action potential propagates across the sarcolemma, preparing the muscle fibers for contraction. As the fibers enter the contraction phase, the...
The latent period of contraction marks the onset of excitation-contraction coupling, when the action potential propagates across the sarcolemma, preparing the muscle fibers for contraction. As the fibers enter the contraction phase, the...
01:22Muscle Stimulation Frequency
The contraction strength of muscles is regulated by motor neurons, which modulate the frequency of action potentials dispatched to the motor units based on the body's requirements. This process of varying the muscle stimulation frequency allows muscles to contract with a force that is precisely tailored to the needs of the moment, whether lifting a feather or a heavy box.
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
01:28Action Potential: Phases of Stimulation
The action potential is a complex electrical event that occurs in excitable cells, such as neurons and muscle cells. It consists of several distinct phases, each with specific characteristics.
Resting Phase:
In this phase, the cell's membrane is at its resting potential, typically around -70 millivolts (mV) for neurons. Inside the cell, there is a higher concentration of potassium ions (K+) and a lower concentration of sodium ions (Na+). Voltage-gated sodium channels are closed, and...
Resting Phase:
In this phase, the cell's membrane is at its resting potential, typically around -70 millivolts (mV) for neurons. Inside the cell, there is a higher concentration of potassium ions (K+) and a lower concentration of sodium ions (Na+). Voltage-gated sodium channels are closed, and...
01:22Isotonic and Isometric Muscle Contractions
Two primary types of muscle contractions are isotonic and isometric, each serving unique functions and involving distinct mechanisms. Both isotonic and isometric contractions are integral to the body's complex system of movement and stability. Isotonic exercises contribute significantly to functional strength and movement, while isometric contractions are crucial for maintaining posture and joint stability.
Isotonic contractions
Isotonic contractions occur when a muscle changes length while the...
Isotonic contractions
Isotonic contractions occur when a muscle changes length while the...
01:13Structure and Organization of Smooth Muscles
Smooth muscle tissue is a type of muscle tissue that can be found lining various vital organs in the human body, including the lungs, blood vessels, digestive tract, and respiratory tract. This type of tissue is responsible for regulating the movements of these organs, playing crucial roles in the functioning of various systems, including the vascular, digestive, respiratory, and urinary systems.
Structure of smooth muscle cell
Smooth muscle cells are spindle-shaped with tapering ends and a...
Structure of smooth muscle cell
Smooth muscle cells are spindle-shaped with tapering ends and a...