Spinal shock is an initial period of “hypotonia” that can result from damage to the motor cortex or other brain regions concerned with the activation of motor neurons. more...
Since many of the descending motor nerves cross the midline, spinal shock originating from damage on one side of the brain (such as damage due to a stroke) can often be detected as reduced muscle activity on the contralateral side of the body. Loss of muscle function tends to be most severe in the arms and legs. Some control of trunk muscles is often preserved because of remaining brainstem pathways and spinal circuits that control midline musculature.
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