Ask the experts
What are Jacksonian seizures?
Jacksonian seizures are brief alterations in movement, sensation or nerve function caused by abnormal electrical activity in a localized area of the brain.
Seizures of this type typically cause no change in awareness or alertness. They are temporary, fleeting, ephemeral.
Jacksonian seizures are extremely varied. They can for example involve head turning, eye movements, lip smacking, mouth movements, drooling, rhythmic muscle contractions in a part of the body, apparently purposeful movements, abnormal numbness, tingling, and a crawling sensation over the skin.
These seizures are named for the English neurologist John Hughlings Jackson who studied speech defects in brain disorders and confirmed the location of the speech center ("Broca's center") in the brain. He described what are today called Jacksonian seizures in 1863 and in 1875 found the areas in the brain that cause them. John Hughlings Jackson was among the great figures of 19th-century medicine.