A functional seizure is an episode that looks like an epileptic seizure, with shaking, altered awareness, or unusual movements, but is not caused by the abnormal electrical activity in the brain that defines epilepsy. The brain’s structure is intact; the problem lies in how the nervous system functions, similar to a software glitch rather than damaged hardware. Functional seizures fall under the broader category of functional neurological disorder (FND), and they are more common than many people realize.
How Functional Seizures Differ From Epilepsy
In an epileptic seizure, neurons fire in abnormal, synchronized bursts that show up clearly on an EEG (a test that records brain electrical activity). During a functional seizure, that abnormal electrical pattern is absent. The brain’s wiring and structure are normal, but the way different brain networks communicate with each other temporarily goes wrong. The result can look nearly identical to epilepsy from the outside, which is why functional seizures are frequently misdiagnosed.
Several physical features tend to distinguish functional seizures from epileptic ones, though none of these signs is absolute on its own:
- Eye closure during the episode. People having an epileptic seizure typically have their eyes open, while eyes-closed shaking is more common in functional seizures.
- Side-to-side head movement rather than the rigid, rhythmic jerking typical of many epileptic seizures.
- Longer duration. Functional seizures often last several minutes or longer, while most epileptic seizures resolve within one to two minutes.
- Shaking with preserved awareness. Some people remain partially aware of their surroundings during a functional seizure, even while their whole body shakes.
- Hyperventilation and pelvic thrusting, which are less common in epileptic seizures.
Why They Happen
Functional seizures are not “faked” or done on purpose. They are involuntary events that the person cannot control. The exact mechanism is still being refined, but the current understanding is that these seizures involve a disruption in the brain’s ability to regulate its own activity, particularly in areas that control movement, sensation, and awareness. Think of it as the brain sending the wrong signals at the wrong time, not because of damage, but because of a malfunction in how networks coordinate.
A strong body of research links functional seizures to psychological and emotional stressors, though not everyone with functional seizures has an obvious trauma history. In large studies, emotional neglect appears in roughly 49% of people with FND, physical abuse in about 30%, and sexual abuse in around 24%. Stressful life events such as a loved one’s death, serious illness, violence, or custody disputes are common triggers. Around 61% of people with functional seizures or FND also meet criteria for post-traumatic stress disorder.
Other psychiatric conditions frequently co-occur. Depression rates in studies of functional seizures range from about 9% to 85% depending on the population studied, and anxiety from 4.5% to 70%. Personality disorders, particularly borderline personality disorder, show up at significantly higher rates than in the general population. Conditions like ADHD, OCD, dissociative disorders, and fibromyalgia also appear more often. This does not mean these conditions cause functional seizures directly, but they seem to share overlapping vulnerabilities, likely rooted in how early stress and trauma reshape the nervous system over time.
How Functional Seizures Are Diagnosed
The gold standard is video-EEG monitoring, where you stay in a specialized unit while both a video camera and EEG electrodes record what happens during a typical episode. If the EEG shows no epileptic electrical activity during an event that looks like a seizure on camera, that confirms a “documented” or definite functional seizure. The American Academy of Neurology identifies this as the most reliable way to distinguish functional seizures from epilepsy.
When video-EEG capture of a typical event is not possible, doctors can still make a diagnosis of “probable” functional seizures based on the clinical history, the pattern of movements during episodes, and routine EEG results between events. But because some people have both epilepsy and functional seizures (a surprisingly common overlap), capturing an actual episode on video-EEG provides the highest level of certainty.
Treatment and Recovery
Because functional seizures are not caused by abnormal electrical activity, anti-seizure medications used for epilepsy do not help and can cause unnecessary side effects. Treatment instead focuses on the underlying nervous system dysfunction and any contributing psychological factors.
Cognitive behavioral therapy (CBT) is the best-studied treatment. A meta-analysis of randomized controlled trials found that people receiving CBT were roughly twice as likely to become seizure-free compared to those receiving standard medical treatment alone. CBT also reduced anxiety and improved overall quality of life. The therapy typically helps people identify triggers, understand the connection between stress and physical symptoms, and develop strategies to interrupt the cycle that leads to seizures.
Comprehensive care often involves a team: a neurologist to confirm the diagnosis and rule out epilepsy, a psychologist or psychiatrist to address trauma, mood disorders, or anxiety, and sometimes a social worker to help with practical challenges like work accommodations or navigating the healthcare system. Physical therapy can also play a role when functional seizures are accompanied by other functional neurological symptoms like weakness or movement problems.
Long-Term Outlook
Recovery varies widely, and being honest about the numbers matters. Across 18 studies tracking adults after diagnosis, about 40% or fewer achieved full seizure remission. The largest study, following 260 patients, found that 38% were seizure-free within 6 to 12 months of diagnosis. That means a majority of adults continue to have some seizures, though many experience a significant reduction in frequency and severity even if they don’t stop entirely.
Children do considerably better. Around 70% of young people with functional seizures achieve remission, likely because the developing brain is more adaptable and because the contributing psychological factors have had less time to become entrenched.
Several factors seem to improve the odds: receiving a clear, early diagnosis; accepting and understanding the diagnosis rather than seeking alternative explanations; engaging in therapy; and having fewer co-occurring psychiatric conditions. The diagnostic conversation itself can be therapeutic. When a doctor explains the condition clearly and without judgment, some people experience an immediate reduction in seizure frequency.
What to Do During a Functional Seizure
First aid for a functional seizure is essentially the same as for an epileptic seizure. Keep the person safe from injury, put something soft under their head if they have fallen, do not restrain them or hold them down, and stay with them until the episode passes. You do not need to call an ambulance for a known functional seizure unless the person is injured, the episode is unusually prolonged, or you are unsure whether it might be epileptic.
After the episode, the person may feel confused, exhausted, or embarrassed. A calm, matter-of-fact response helps more than alarm or excessive concern. Functional seizures are real neurological events, and treating them that way, both during and after, supports recovery.