upper motor neuron
Brain's movement messenger
Upper motor neurons are nerve cells in the brain and brainstem that control voluntary movement by sending signals down the spinal cord to lower motor neurons.
They originate in the motor cortex and travel through pathways like the corticospinal tract.
When upper motor neurons are damaged, the result is typically spasticity, increased reflexes, and weakness—distinct from the flaccid paralysis seen with lower motor neuron injuries.
The patient's hyperreflexia suggested upper motor neuron involvement.
- spasticityPathological muscle tightness
- muscle stiffnessReduced flexibility in tissue
- paralysisLoss of muscle function
- weaknessDeficiency in force
- pyramidalHaving four triangular faces
brainstem · reflex · Babinski · clonus · stroke · ALS · descending · tract · lesion · voluntary · movement · rigidity · paresis · hemiplegia · muscle tone · spinal cord · brain · brain injury
- motor systemvoluntary movement