Our current conceptualization is that the condition arises as a behavioral response to underlying emotional or psychological distress. Episodes may be derived from traumatic experiences in early life, particularly physical, sexual, and mental abuse during childhood but such is not always the case. Many experts consider them to be allied with hysteria (Briquet disease, conversion disorder, as discussed in Chap. 47) or malingering. Recent studies suggest that a conversion-hysterical disorder accounts for most cases, and that malingering is rare but this is difficult to prove.
Three broad categories of psychogenic states seem to generate pseudoseizures: (1) panic disorder that is itself common in people with epilepsy; (2) dissociative disorders, in which convulsions are typically prolonged, resembling generalized tonic-clonic seizures, or alternatively, swooning as in a faint or presyncopal spell, or blank spells that closely simulate absence seizure; and (3) malingering, the deliberate feigning of seizures to avoid certain situations, for example, imprisonment.
Usually, the unconventional motor display in the course of a nonepileptic seizure is sufficient to identify it as such: completely asynchronous thrashing of the limbs and repeated side-to-side movements of the head; striking out at a person who is trying to restrain the patient; hand-biting, kicking, trembling, and quivering; pelvic thrusting and opisthotonic arching postures; and screaming or talking during the ictus. It is helpful to observe that the eyes are kept quietly or forcefully closed in pseudoseizure whereas the lids are open or show clonic movement in epilepsy. Psychogenic spells are likely if attacks are prolonged (many minutes, even hours), if there is rapid breathing (whereas apnea is typical during and after a seizure), or if there is tearfulness after an episode. Psychogenic seizures tend to occur in the presence of observers, to be precipitated by emotional factors. With few exceptions, tongue-biting, incontinence, hurtful falls, or postictal confusion are lacking but if the tongue is bitten in one of these spells it is usually the front, compared to the lateral tongue injury that is characteristic of an epileptic attack. Incontinence does not assist in making a clear distinction from epileptic seizures.
Another clue to nonepileptic seizures has been highly resistant epilepsy in an individual with normal cognitive function and normal brain imaging. Sometimes there has been a background of unexplained medical problems, previous psychological problems (depression, panic disorder, overdose, self harm, addiction), and a life story that includes intense emotional trauma. Prolonged fugue states usually prove to be manifestations of hysteria or a psychopathy, that is, a dissociative state, even in a known epileptic.
The serum creatine kinase levels are normal after nonepileptic seizures; this may be helpful in distinguishing them from epilepsy. Where doubt remains, a recording of the ictal or postictal EEG or prolonged combined video and EEG recording of an attack may settle the issue. The treatment of these patients requires a patient, nonjudgmental and multidisciplinary approach with the goal of reducing disability and hospital admission and eliminating unnecessary medications.
Physiologically, the epileptic seizure has been defined as a sudden alteration of central nervous system (CNS) function resulting from a paroxysmal high-frequency or synchronous low-frequency, high-voltage electrical discharge. This discharge arises from an assemblage of excitable neurons in any part of the cerebral cortex and possibly in secondarily involved subcortical structures as well. In the proper circumstances, a seizure discharge can be initiated in an entirely normal cerebral cortex, as when the cortex is activated by ingestion of drugs, or by withdrawal from alcohol or other sedative drugs. A special mechanism that ostensibly creates a secondary seizure focus, “kindling,” is the result of repeated stimulation with subconvulsive electrical pulses from an established focus elsewhere; it is known to occur in animal models but is a controversial entity in humans.