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Characteristics that distinguish upper motor neuron lesions from lower motoneuron lesions is (are) (assume the lesions are total):

A. reflex movements are possible with upper but not lower motoneuron lesions.
B. fibrillation potentials in the EMG are present in upper but not lower motoneuron lesions.
C. there is eventual severe muscle degeneration with wasting of muscle tissue with upper motoneuron lesions.
D. all of the above
E. A and C only

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a.

other opinions?

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A is Correct: Upper motoneuron lesions result in paralysis (loss of voluntary control) and hyperreflexia. The muscles remain connected to the central nervous system, but higher centers are disconnected from lower centers. Reflexes work but voluntary control is lost. Lower motoneuron lesions disconnect the muscles from the CNS.