Specialist expertise: Sleep Disorders, Epilepsy, Neurology, Headache.
The term “blackout” refers to any alteration of awareness or consciousness, and blackouts may have a wide range of causes. Blackouts may be as a result of sudden drops in blood pressure as in fainting, may have a cardiac cause, can be seen in sleep disorders, can have a psychological cause or may be as a result of neurological dysfunction, such as a seizure.
Seizures represent the sudden development of unregulated abnormal electrical activity within the brain. These uncontrolled electrical discharges result in a temporary disruption of neurological function. Depending on where in the brain and how widespread this electrical activity is, seizures may result in minor symptoms such as brief speech disturbance, tremor, or confusion, but if the electrical activity spreads throughout the brain, a generalised convulsion may result.
Epilepsy describes the tendency to have recurrent seizures in the absence of a clear physical trigger, and is usually diagnosed in this setting after two or more seizures. Occasionally epilepsy may be diagnosed after a single seizure, if investigations point to a high likelihood of another seizure.