Search results
Results From The WOW.Com Content Network
A neuromuscular junction (or myoneural junction) is a chemical synapse between a motor neuron and a muscle fiber. [1] It allows the motor neuron to transmit a signal to the muscle fiber, causing muscle contraction. [2] Muscles require innervation to function—and even just to maintain muscle tone, avoiding atrophy. In the neuromuscular system ...
A motor nerve, or efferent nerve, is a nerve that contains exclusively efferent nerve fibers and transmits motor signals from the central nervous system (CNS) to the muscles of the body. This is different from the motor neuron , which includes a cell body and branching of dendrites, while the nerve is made up of a bundle of axons.
A motor neuron (or motoneuron or efferent neuron [1]) is a neuron whose cell body is located in the motor cortex, brainstem or the spinal cord, and whose axon (fiber) projects to the spinal cord or outside of the spinal cord to directly or indirectly control effector organs, mainly muscles and glands. [2]
A neuroeffector junction is a site where a motor neuron releases a neurotransmitter to affect a target—non-neuronal—cell. This junction functions like a synapse.However, unlike most neurons, somatic efferent motor neurons innervate skeletal muscle, and are always excitatory.
Nerve conduction studies can only diagnose diseases on the muscular and nerve level. They cannot detect disease in the spinal cord or the brain. In most disorders of the muscle, nerve, or neuromuscular junction, the latency time is increased. [12] This is a result of decreased nerve conduction or electrical stimulation at the site of the muscle.
Perisynaptic Schwann Cells (PSCs) contribute to the tripartite synapse organization in combination with the pre-synaptic nerve and the post-synaptic muscle fiber. [1] PSCs are considered to be the glial component of the Neuromuscular Junction (NMJ) and have a similar functionality to that of Astrocytes in the Central Nervous System . [ 2 ]
In vertebrates, the force of a muscle contraction is controlled by the number of activated motor units. The number of muscle fibers within each unit can vary within a particular muscle and even more from muscle to muscle: the muscles that act on the largest body masses have motor units that contain more muscle fibers, whereas smaller muscles ...
Glutamate released from the upper motor neurons triggers depolarization in the lower motor neurons in the anterior grey column, which in turn causes an action potential to propagate the length of the axon to the neuromuscular junction where acetylcholine is released to carry the signal across the synaptic cleft to the postsynaptic receptors of the muscle cell membrane, signaling the muscle to ...