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Movement and daily function

Upper motor neuron

The nerve cells running from the brain down the spinal cord. When they are affected, muscles become stiff and reflexes become exaggerated.

What it means

Movement travels along two relays. The upper one carries the instruction from the brain to the spinal cord. When it is affected, muscles become stiff and reflexes become exaggerated, because the signal that normally damps them down is weaker.

Why you might hear it

  • Neurologists use it to describe examination findings.
  • The mix of upper and lower findings is part of how a diagnosis is reached.

People who may help

Where Compass goes into this

About this explanation

These are plain explanations of words you may come across, not advice about your own situation. Where a word matters to a decision, the question pages go into it properly, and your own team is the place to take it.