Partial complex seizure

Alternative names:

complex seizure; seizure - complex

Definition:

A brief, temporary alteration in brain function caused by abnormal electrical activity in the nerve cells of a discrete area of the brain, characterized by change in alertness or awareness with behavioral or emotional symptoms and temporary loss of memory. See also temporal lobe seizure.

Causes, incidence, and risk factors:

Partial complex seizures affect approximately 1 to 5 out of 1,000 people. They may occur at any age, as a single episode or as a repeated, chronic condition (seizure disorder, epilepsy). They are uncommon in very young children, but the incidence is similar to adults after about 8 to 10 years of age.

Transmission of information from nerve cell to nerve cell occurs by an electrochemical process. This process can be detected as electrical activity by an electroencephalograph (EEG). Abnormal patterns of electrical activity are associated with seizures. Given sufficient circumstances, any person will have a seizure. Partial complex seizures are most commonly the result of abnormal electrical activity in the temporal lobes of the brain. Psychic symptoms may occur, along with a decrease in the level of consciousness.

Specific causes of partial complex seizures most commonly include localized areas where there has been damage caused by lack of oxygen, trauma, or by brain tumors or discrete brain lesions of any sort. Pathological review of temporal lobes removed from children with partial complex seizures showed hippocampal sclerosis (hardening in the area of the brain called the hippocampus) to be the most common consistent finding (about 47%).