Related Experiment Video

Updated: Aug 11, 2026

Simultaneous Intracellular Recording of a Lumbar Motoneuron and the Force Produced by its Motor Unit in the Adult Mouse In vivo
13:07

Simultaneous Intracellular Recording of a Lumbar Motoneuron and the Force Produced by its Motor Unit in the Adult Mouse In vivo

Published on: December 5, 2012

Coherent modulations of human motor unit discharges during quasi-sinusoidal isometric muscle contractions

M B Iyer1, C N Christakos, C Ghez

  • 1Center for Neurobiology and Behavior, New York State Psychiatric Institute, College of Physicians and Surgeons, Columbia University, New York 10032.

Neuroscience Letters
|March 28, 1994
PubMed

More Related Videos

Functional Isolation of Single Motor Units of Rat Medial Gastrocnemius Muscle06:54

Functional Isolation of Single Motor Units of Rat Medial Gastrocnemius Muscle

Published on: December 26, 2020

In Vivo Measurement of Hindlimb Dorsiflexor Isometric Torque from Pig09:41

In Vivo Measurement of Hindlimb Dorsiflexor Isometric Torque from Pig

Published on: September 3, 2021

Related Concept Videos

Excitation-Contraction Coupling in Skeletal Muscles01:20

Excitation-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...
Motor Units01:13

Motor Units

The motor unit is a fundamental component of the neuromuscular system and plays a crucial role in coordinating muscle contractions. It consists of a somatic motor neuron, which connects and controls multiple skeletal muscle fibers, forming a single functional segment. The axon of the motor neuron branches out and establishes synaptic connections known as neuromuscular junctions with individual muscle fibers within the motor unit.
Motor units come in different sizes, with smaller units...
Motor Unit Stimulation01:20

Motor 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...
Muscle Stimulation Frequency01:22

Muscle 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...
Isotonic and Isometric Muscle Contractions01:22

Isotonic 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...
Smooth Muscle Contraction01:25

Smooth Muscle Contraction

Smooth muscle contraction is a complex process vital for various bodily functions, from maintaining blood vessel tension to facilitating the movement of food through the digestive tract. Unlike striated muscles, smooth muscle contraction begins more slowly and lasts longer.
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...