A sudden attack, spasm, or convulsion, as in epilepsy or another disorder. There are many types of seizure activity:

  • absence seizure (petit mall seizuremarked by a momentary break in the stream of thought and activity, accompanied by a symmetrical spike and wave at 3 cycles per second on the electroencephalogram.
  • adversive seizure  a type of focal motor seizure in which there is forceful, sustained turning to one side by the eyes,head, or body.
  • atonic seizure an absence seizure characterized by sudden loss of muscle tone.
  • complex partial seizure  a seizure stemming from a localized part of the brain indicated by the presence of a state similar to a trance,varying degrees of awareness, and the manifestation of purposeless behaviors or motions.The seizure may be followed by an indeterminate period of confusion, garbled speech, poor mood, and an inability to recall the events of the episode.
  • focal motor seizure a simple partial seizure consisting of clonus or spasm of a muscle or muscle group, occurring either singly or in a continuous repetitive series.
  • tonic-clonic seizure (grand mal seizure) marked by loss of consciousness and generalized tonic convulsions followed by clonic convulsions.