24 Functional Seizures
24.1 What Are Functional Seizures?
Functional seizures are episodes that look like epileptic seizures but are not caused by abnormal electrical activity in the brain. They are real and involuntary: the person having them is not faking or exaggerating. They have no control over the episodes1.
This condition is more common than many people realize. Some estimate that about 1 in 5 patients sent to an epilepsy specialist for seizures that don’t respond to medication turn out to have functional seizures2.
24.2 A note on terminology
Over the years, this condition has had many names. You may have seen or heard:
- Pseudoseizures
- Hysterical seizures
- Non-epileptic attack disorder (NEAD)
- Psychogenic non-epileptic seizures (PNES)
- Dissociative seizures
- Conversion disorder
These older terms may still be found in medical records and online. Many of them are stigmatizing: for example, “pseudoseizures” implies the episodes are fake, which they are not.
The current recommended terms are “functional seizures” or “functional/dissociative seizures (FDS)”2,3. This handbook uses “functional seizures” throughout.
24.3 Why Do They Happen?
The brain and the body are closely linked. When we feel strong emotions like fear, grief, or stress, our body can have physical reactions: the heart beats faster, muscles tighten, breathing changes. This is normal.
In some people, emotional distress gets expressed as physical symptoms, including seizure-like episodes. This happens without the person choosing it or even being aware of it. It is called somatization1.
The distress behind functional seizures can take many forms:
- Ongoing life stress
- A history of trauma
- Depression or anxiety
- A physical illness or injury
The episodes are not “in the imagination.” They reflect a real change in how the brain is working, even when scans look normal. Importantly, they do not result in a change in brain electrical patterns like what we see in epileptic seizures.
24.4 How Are They Different from Epileptic Seizures?
Both types of seizure can look similar, and a specialist is needed to tell them apart. In some people, both types are present at the same time1.
Some features that may point toward functional seizures include:
- Eyes closed during the episode (in epileptic seizures, eyes are usually open)
- Long duration: often several minutes or more
- Irregular movements that vary from episode to episode, rather than following the same pattern each time
- Side-to-side head movements or pelvic thrusting
- Staying aware even during dramatic movements
- Quick recovery after the episode ends
- Triggered by stress or strong emotions
None of these features alone is enough to make the diagnosis2.
24.5 How Is the Diagnosis Made?
The main test is called video-EEG monitoring. This records the brain’s electrical activity and a video of the person at the same time, while waiting for an episode to happen naturally.
In epileptic seizures, the EEG shows abnormal electrical activity during the episode. In functional seizures, the EEG stays normal: even during a dramatic episode2.
A full assessment also usually includes:
- A detailed history from the patient and someone who has witnessed the episodes
- Review of previous EEGs and brain scans
- A psychological assessment to understand possible contributing factors
Ideally, we can capture the seizures in question and review the EEG during episodes to determine if they are epileptic or functional. However, depending on the frequency of seizures, we may not always be able to capture an event during a video-EEG test. In this case, your doctor may still be able to make the diagnosis of functional seizures after reviewing the seizures by history and/or video, together with prolonged normal EEG recordings (typically 2-3 nights).
24.6 Is This a Mental Health Diagnosis?
Functional seizures are part of a broader group of conditions called functional neurological disorder (FND). In FND, the brain is not working properly, but no structural damage can be found. The problem is in how the brain’s circuits are functioning, not in the brain tissue itself1,2.
This means the condition is not imaginary, not deliberate, and not simply depression or anxiety, though those can be contributing factors.
Many patients feel relief when they get a clear diagnosis. Finally, there is a name and an explanation for what has been happening. Others feel upset, especially if they have been told for years they had epilepsy. Both responses make complete sense.
24.7 Treatment
Functional seizures are treatable. The goal is to address the underlying distress and help the brain break the pattern of episodes1.
24.7.1 Understanding the Diagnosis
One of the most important steps is getting a clear, kind explanation of the diagnosis. Knowing that the episodes are real and have a neurological basis, not structural brain damage, is a key starting point for recovery1.
24.7.2 Talking Therapy
Because underlying emotional or psychological distress plays a central role, therapy is usually the main treatment:
- Cognitive behavioural therapy (CBT): the most well-studied option. A large clinical trial (the CODES study) showed it helps reduce seizure frequency4. CBT helps patients notice the thoughts, feelings, and situations linked to their episodes, and build new ways of coping.
- Trauma-focused therapy: when trauma is a key factor
- Mindfulness-based approaches: can help with stress and body awareness
The right therapy depends on the person. There is no single approach that works for everyone2.
24.7.3 Treating Other Conditions
Many people with functional seizures also have depression, anxiety, or PTSD. Treating these with therapy, medication, or both is an important part of overall care2.
24.7.4 Physiotherapy
For people who have become less active due to their seizures, physiotherapy can help rebuild strength and confidence.
24.7.5 Do Antiseizure Medications Help?
No. Antiseizure medications do not treat functional seizures and should not be started for this reason. Many patients are placed on these drugs before the diagnosis is clear. Coming off them safely needs to be done with specialist guidance2.
24.8 Day-to-Day Life
Most people with functional seizures improve significantly with the right care4. Recovery takes time, and some setbacks along the way are normal.
Some practical points:
- Driving: The same restrictions that apply to epilepsy generally apply to functional seizures until episodes are well controlled. Talk to your neurologist.
- Safety: While seizures are frequent, the same precautions as for epilepsy apply: avoid unsupervised swimming, heights, and unsupervised bathing.
- Work and activity: Most people can return to normal activity. A gradual return, with support, often works best.
- Family and support: Helping a close person understand the diagnosis can reduce anxiety and improve the support you receive.
24.9 Stigma
For a long time, patients with functional seizures were told their symptoms were “not real,” or that it was “all in their head.” This often caused real harm5.
Functional seizures are real. The brain is an organ, and when it is not functioning properly, for any reason, the suffering is just as real as in any other illness. Every patient deserves a clear diagnosis, a kind explanation, and access to good treatment1.
24.10 Key Points
- Functional seizures look like epileptic seizures but are caused by a different process. They are not caused by abnormal electrical activity in the brain
- They are real and involuntary. Not faking, not “in the head”
- The recommended term is now “functional seizures” or “functional/dissociative seizures”; older terms like PNES are out of date
- Video-EEG monitoring is the main diagnostic test
- Treatment centres on talking therapy and addressing underlying distress
- Most people improve significantly with the right care