atonic seizure

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Related to atonic seizure: absence seizure, Clonic seizure, Tonic clonic seizure


1. the sudden attack or recurrence of a disease.
2. a convulsion or attack of epilepsy.
absence seizure the seizure seen in petit mal epilepsy, marked 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. Called also petit malseizure. See epilepsy.
atonic seizure an absence seizure characterized by sudden loss of muscle tone.
complex partial seizure see partial seizure.
febrile seizure febrile convulsion.
focal seizure partial seizure.
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.
generalized tonic-clonic seizure (grand mal seizure) the seizure seen in grand mal epilepsy, marked by loss of consciousness and generalized tonic convulsions followed by clonic convulsions. See epilepsy.
jackknife s's infantile spasms.
myoclonic seizure one characterized by a brief episode of myoclonus.
partial seizure any seizure due to a lesion in a specific, known area of the cerebral cortex; symptoms vary with different lesion locations. A simple partial seizure is the most localized type, with a discharge that is predominantly one-sided or presents localized features without loss of consciousness. A complex partial seizure is associated with disease of the temporal lobe and characterized by varying degrees of impairment of consciousness. See epilepsy.
petit mal seizure absence seizure.
reflex seizure (sensory seizure) an epileptic seizure in response to a sensory stimulus, which may be tactile, visual, auditory, or musical.
simple partial seizure see partial seizure.
tonic-clonic seizure see generalized tonic-clonic seizure.

a·ton·ic sei·zure

a seizure characterized by sudden, brief (1-2 second) loss of muscle tone, involving postural muscles; the term usually applies to bilaterally synchronous events.
Synonym(s): akinetic seizure
References in periodicals archive ?
Not to mention, he started to experience, at the time, what are called atonic seizures (drop-attack seizures of paralysis).
Falling is the main concern with generalized tonic-clonic seizures (either primary or partial seizures that secondarily generalize) and atonic seizures.
Tonic and atonic seizures, also known as "drop attacks," cause the body to fall uncontrollably, and are a primary cause of facial and head injuries as well as lacerations that can leave disfiguring scars.
Atonic seizures (rapid loss of muscle tone and consciousness), and tonic seizures (where muscles contract continuously typically producing a stiffening of the legs and arms) lead to the sudden falls seen in LGS patients known as 'drop attacks'.