Motor neuron

motor neuron

n.

A neuron that conveys impulses from the central nervous system to a muscle, gland, or other effector tissue.

---

Motor neuron

Nerve cells within the central nervous system that carry nerve impulses controlling muscle movement.

Mentioned in: Amyotrophic Lateral Sclerosis, Muscle Spasms and Cramps

---

motor neuron

a neuron having a motor function; an efferent neuron conveying motor impulses.

---

motor neuron disease

see abiotrophy.

equine motor neuronn. disease

(EMND) a syndrome of mature horses of uncertain etiology, but possibly an oxidative disorder associated with insufficient green forage in the diet and a deficiency of vitamin E. Characterized by generalized weakness, muscle fasciculations and weight loss, despite a normal appetite, that is caused by neurogenic muscle atrophy. There is also a distinctive retinopathy.

lower motor neuron n's

peripheral neurons whose cell bodies lie in the ventral gray columns of the spinal cord and whose terminations are in skeletal muscles. Called also LMN. See also lower motor neuron.

peripheral motor neuron n's

neurons in a peripheral reflex arc that receive impulses from interneurons and transmit them to voluntary muscles.

upper motor neuron n's

neurons in the cerebral cortex that conduct impulses from the motor cortex to the motor nuclei of the cerebral nerves or to the ventral gray columns of the spinal cord. Lesions of the upper motor neuron interrupt the inhibitory effect that upper motor neurons have on lower motor neurons, resulting in exaggerated or hyperactive reflexes. This is called also extensor rigidity. See also upper motor neuron. Called also UMN.