Reversible disability associated with epilepsy.

Epilepsy is a syndrome complex in which the impairments include seizures, cognitive arrest and regression, psychiatric illness, and motor and visual disorders. In both lesional and non-lesional epilepsy there is evidence of reversibility of these impairments in some patients which provides compelling evidence that there is a dynamic pathogenetic mechanism which can 'take-out' discreet or global cortical functions. The best evidence that we have suggests that seizures themselves particularly sub-clinical seizure activity are the major factor. Numerous examples of partial and even complete recoveries as a result of medical and surgical treatments are now available. These support the notion that in addition to direct seizure activity there is a pervasive element to the syndromes of epilepsy which causes anything from mild attention deficit or difficulties with language processing to catastrophic loss of cognitive and social functioning. The malignant seizure syndromes are mostly defined by the high risk of these impairments. The challenge of the developmental epilepsies is to explore the pathogenesis and develop new treatments. Perhaps the most difficult aspect of this work is to understand the critical periods for recovery and thus how to avoid irreparable damage.