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Seizures happen when brief episodes of abnormal electrical activity disrupt the brain’s normal function.
They are generally classified as focal or generalized. Focal seizures begin in a particular area of the brain.
When awareness is preserved, a person may feel tingling, see flashing lights, or smell something unusual.
If awareness is impaired, the person may stare blankly or perform repetitive movements like lip-smacking.
Some focal seizures can spread to both sides of the brain, becoming focal to bilateral tonic-clonic seizures, which involve stiffening and rhythmic jerking.
Generalized seizures engage both sides of the brain from the onset and always impair awareness.
These include tonic-clonic seizures, which involve muscle stiffening followed by rhythmic jerking and often cause loss of consciousness, and absence seizures, where the person suddenly stops and stares.
These also include myoclonic jerks, tonic stiffening, clonic rhythmic movements, and atonic seizures, called drop attacks, that cause sudden collapse.
Seizures are sudden bursts of abnormal electrical discharge in the brain that interfere with normal function. They are commonly divided into three gro…
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