Identifying the Difference Between Functional Seizures and Epileptic Seizures

Contemporary Clinic® interviewed Lea Davis, PhD, an associate professor of medicine in the Department of Medicine at Vanderbilt University Medical Center and an investigator in the Vanderbilt Genetics Institute, on a recent study she co-authored that was published in JAMA Network Open on the epidemiology of functional seizures among adults treated at a university hospital.

During the discussion, Davis addressed the difference between functional seizures and epileptic seizures in patients, and how providers can identify this difference.

Alana Hippensteele: What exactly is the difference between functional seizures and epileptic seizures in patients, and what methods are available to identify the difference?

Lea Davis: So, the seizure itself can look very similar. Functional seizures often look like grand mal seizures, and they can be really difficult to distinguish from epileptic seizures, even for experts who are well-trained in understanding functional seizures. Really the gold standard for being able to diagnose functional seizures is a video EEG, which means that somebody is under video observation, and they have the cap with all the wires attached to their scalp to measure electrical activity, and this can often take 2 or 3 days of a person being under observation, where they're basically just waiting for a typical seizure—a seizure like the kind that the patient typically experiences, and then they look to see [if] those seizures also correspond with electrical activity in the brain that is a signature of epilepsy or not. If it does not correspond with aberrant brain activity that is indicative of epilepsy, then it's classified as a functional seizure.