[Neurophysiology in Guillain-Barré syndrome]

The electrodiagnostic features for the demyelinating and axonal subtypes of Guillain-Barré syndrome (GBS) were described. In the early stage of demyelinating GBS, the most prominent neurophysiologic feature is the patchy demyelination in the peripheral nerves. Conduction slowing presents in the clinical recovery stage, which indicates the conduction slowing is due to mainly remyelination. Axonal GBS shows "reversible conduction failure", as well as primary axonal degeneration. "Reversible conduction failure" is thought to be the most common cause of the underestimation of axonal GBS. The electrodiagnostic criteria for GBS subtypes should be revised based on the knowledge acquired in recent years.