Non-epileptic seizures (NES) are episodes that appear similar to true epileptic seizures, often involving sudden movements, unresponsiveness, or altered awareness. The defining difference is that NES are not caused by the abnormal electrical discharges in the brain that characterize epilepsy. Instead, NES are a manifestation of underlying psychological distress or functional neurological disorder. Understanding how these events differ from epilepsy is the first step toward receiving the correct diagnosis and appropriate treatment.
Defining Non-Epileptic Seizures
Non-epileptic seizures are a category of events that mimic epileptic seizures but arise from causes other than abnormal brain electrical activity. The most common type is Psychogenic Non-Epileptic Seizure (PNES), which falls under the umbrella of functional neurological disorders (FND). PNES is a physical manifestation of psychological distress, where emotional or psychological stressors are converted into physical symptoms. These events are involuntary and genuine physical reactions to overwhelming psychological states, and are not consciously controlled or faked by the individual.
The origin of these events is often linked to a history of trauma, psychological conflict, or chronic emotional stress. Although the term “pseudoseizures” was used historically, it is now considered misleading because the symptoms are very real to the person experiencing them.
Distinct Physical Manifestations
The observable features of a non-epileptic seizure can vary widely between individuals. A common manifestation involves asynchronous movements, where the limbs on both sides of the body move in an uncoordinated, out-of-sync manner. This often presents as thrashing, flailing, or side-to-side shaking of the head or body, rather than the rhythmic stiffening and jerking seen in generalized epilepsy. The intensity of the motor activity can fluctuate significantly during the episode, a pattern rarely observed in epileptic events.
NES episodes frequently last much longer than typical epileptic seizures, sometimes persisting for several minutes or even hours. During the event, patients may exhibit excessive vocalizations, such as crying, screaming, or moaning, reflecting underlying emotional distress. While the person may appear unresponsive, they often show signs of fluctuating or preserved awareness, such as instinctively protecting themselves from injury. Resistance when an observer attempts to gently open the person’s eyelids is also common, indicating retained muscle tone and fluctuating consciousness.
Key Differences from Epileptic Seizures
Distinguishing NES from epileptic seizures relies on careful observation of behavioral characteristics during and immediately following the event. A primary difference concerns eye behavior, as individuals experiencing an NES often keep their eyes tightly closed or resist attempts to open them. In contrast, patients with a generalized epileptic seizure typically have their eyes open and staring, or they may roll back.
The pattern of movement also provides a significant clue, with NES movements often being non-stereotypical, lacking the consistent, repetitive, and synchronized motions seen in true epileptic convulsions. NES movements may also build up gradually, whereas epileptic seizures tend to start abruptly. The post-event state is a major differentiator; in NES, it is typically characterized by immediate clarity or rapid return to a normal level of consciousness. An epileptic seizure, especially a generalized tonic-clonic type, is usually followed by a period of profound post-ictal confusion, disorientation, and deep sleep. Injuries are less common in NES, and when tongue biting occurs, it is often on the tip of the tongue rather than the sides, which is typical of severe epileptic convulsions.
Diagnosis and Therapeutic Approaches
The definitive diagnosis of a non-epileptic seizure requires the use of Video-Electroencephalography (VEEG) monitoring, which is considered the gold standard. This procedure involves continuous video recording of the patient alongside simultaneous electroencephalogram (EEG) monitoring of their brain electrical activity. During a VEEG study, the patient is monitored until a typical seizure-like event occurs and is captured on both the video and the EEG.
If the event is an NES, the video will show the clinical seizure behavior, but the simultaneously recorded EEG will show no abnormal electrical discharges, confirming the non-epileptic nature. Once PNES is confirmed, treatment shifts away from anti-seizure medications, which are ineffective, and focuses on the psychological origin of the symptoms. The current mainstay of treatment is psychotherapy, particularly Cognitive Behavioral Therapy (CBT). CBT aims to help patients understand the link between their stress, emotions, and physical symptoms, reducing the frequency of these episodes and improving overall quality of life.