upper motor neuron

(redirected from Upper motor neurons)

up·per mo·tor neu·ron

clinical term indicating those neurons of the motor cortex that contribute to the formation of the corticospinal and corticonuclear (corticobulbar) tracts, as distinguished from the lower motor neurons innervating the skeletal muscles. Although not motor neurons in the strict sense, these cortical neurons became colloquially classified as motor neurons because their activation produces movement and their destruction causes moderate to severe disorders of movement.
See also: motor neuron, motor cortex.

upper motor neuron

A motor neuron (actually an interneuron) found completely within the central nervous system that synapses with or regulates the actions of lower motor neurons in the spinal cord and cranial nerves. Lesions of these neurons produce spastic paralysis in the muscles they innervate. Synonym: upper motoneuron
See also: neuron

upper

cranial; oral; rostral.

upper airway
upper respiratory tract. See also airway.
upper burner syndrome
in acupuncture terminology a chronic lung condition caused by an attack by a pathogen.
upper motor neuron
motor nerve pathway originating in the brain and terminating at a peripheral motor neuron. Damage to this pathway releases the peripheral nerve from central control. See also upper motor neuron.
upper respiratory tract (URT)
comprises the nasal cavities, pharynx and larynx. Some anatomists also include the upper segments of the bronchial tree. Inflammation of the URT is common to all species. It is usually caused by infection, most commonly viral, producing a syndrome of frequent, dry cough, serous or mucoid nasal discharge and pain on manual compression of the laynx, pharynx and trachea. It is a common precursor to more serious disease involving the lower respirtory tract.
upper respiratory tract virus disease
see Table 8.2.
References in periodicals archive ?
Amanda has co-authored 15 peer-reviewed manuscripts and her research has been supported through grants from NIH, The ALS Association, and most recently, a development grant from MDA to investigate how cells known as upper motor neurons, located in the frontal cortex of the brain, degenerate in ALS.
ALS is a fatal progressive degenerative disease resulting in relentlessly progressive weakness and wasting of voluntary muscles, affecting a combination of the upper motor neurons in the motor cortex and the lower motor neurons in the brainstem and spinal cord.
ALS is a fatal degenerative disease resulting in relentlessly progressive weakness and wasting of voluntary muscles, affecting a combination of the upper motor neurons in the motor cortex and the lower motor neurons in the brainstem and spinal cord.
Upper motor neurons direct the lower motor neurons to produce movements such as walking or chewing.

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