Pathophysiological aspects of the formation of neurological deficit in multiple sclerosis

The results of complex studies were used to formulate a concept of the development of neurological impairments in multiple sclerosis (MS). Acutely developing impairments to spike propagation, reaching the level of conduction blockade, due to the active pathological process with demyelinating and axonal damage to the CNS lead to the formation of neurological impairments in exacerbations of MS, while complete or partial reversion (regression) of these symptoms in the stage of remission results from compensatory changes in the nature of conduction, which were not, however, accompanied by recovery of electrophysiological measures. The development of stable neurological deficit in secondary-progressive MS is determined by impairments to spike conduction processes associated with significant levels of demyelination and atrophic changes in the CNS, with myelin loss and axon death. Finally, the severity of cognitive changes is determined by differences in the severities of both the focal demyelinating process and diffuse damage to brain substance in MS, including the neurodegenerative component. The main factor in transient increases in symptoms is the universal lability of electrophysiological parameters, including those developing on the background of ion and neurotransmitter imbalance. © 2009 Springer Science+Business Media, Inc.