--like a mild case of Guillain Barre syndrome, or one of its variants:

http://neuromuscular.wustl.edu/antibody/gbs.htm

The nerve conduction study showing some evidence of demyelination is a clue there--though I'm glad the EMG did not show evidence of muscle weakness. Do be aware, though, that sometimes this does not show clinically for some weeks after an initial acute attack; motor fibers are deeper within the nerve trunks than sensory fibers and are often slower to show damage or deteriorate when the primary mechanism is loss of the myelin coating of the nerves as opposed to an attack on the nerve fibers (the axons) themselves.

Guillain Barre and its related syndromes are autoimmune in nature; there are some tests, among them the spinal tap, which might show evidence of autoantibody activity.

It's good that the MRI came back normal, as the first thought in these cases is often a central nervous system demyelinating syndrome such as multiple sclerosis. Still, it would behoove your physicians to monitor that and perhaps do follow up MRI's in the future.