This article is from the Epilepsy FAQ, by Andrew Patrick (andrew@calvin.dgbt.doc.ca) with numerous contributions by others.
The brain is a highly complex and sensitive organ. It controls and
regulates all our actions. It controls motor movements, sensations,
thoughts, and emotions. It is the seat of memory, and it regulates the
involuntary inner workings of the body such as the function of the
heart and the lungs.
The brain cells work together, communicating by means of electric
signals. Occasionally there is an abnormal electrical discharge from a
group of cells, and the result is a seizure. The type of seizure will
depend upon the part of the brain where the abnormal electrical
discharge arises.
 
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