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Seizures are purely occipital and primarily manifest with elementary visual hallucinations, blindness or both.
They are usually frequent and diurnal, develop rapidly within seconds and are brief, lasting from a few seconds to 1–3 min, and, rarely, longer.
Elementary visual hallucinations are the most common and characteristic ictal symptoms, and are most likely to be the first and often the only clinical manifestation. They consist mainly of small multicoloured circular patterns that often appear in the periphery of a visual field, becoming larger and multiplying during the course of the seizure, frequently moving horizontally towards the other side.
Other occipital symptoms, such as sensory illusions of ocular movements and ocular pain, tonic deviation of the eyes, eyelid fluttering or repetitive eye closures, may occur at the onset of the seizures or appear after the elementary visual hallucinations. "Deviation of the eyes", often associated with ipsilateral turning of the head, is the most common (in about 70% of cases) nonvisual ictal symptom. It is often associated with ipsilateral turning of the head and usually starts after visual hallucinations, although it may also occur while the hallucinations still persist. It may be mild, but more often it is severe and progresses to hemiconvulsions and secondarily generalised tonic clonic seizures (GTCS). Some children may have seizures of eye deviation from the start without visual hallucinations.
"Forced eyelid closure and eyelid blinking" occur in about 10% of patients, usually at a stage at which consciousness is impaired. They signal an impending secondarily GTCS.
"Ictal blindness", appearing from the start or, less commonly, after other manifestations of occipital seizures, usually lasts for 3–5 min. It can occur alone and be the only ictal event in patients who could, at other times, have visual hallucinations without blindness.
Complex visual hallucinations, visual illusions and other symptoms resulting from more anterior ictal spreading rarely occur from the start. They may terminate in hemiconvulsions or generalised convulsions.
Ictal headache, or mainly orbital pain, may occur and often precedes visual or other ictal occipital symptoms in a small number of patients.
Consciousness is not impaired during the visual symptoms (simple focal seizures), but may be disturbed or lost in the course of the seizure, usually before eye deviation or convulsions.
Occipital seizures of ICOE-G may rarely progress to extra-occipital manifestations, such as hemiparaesthesia. Spread to produce symptoms of temporal lobe involvement is exceptional and may indicate a symptomatic cause.
Post-ictal headache, mainly diffuse, but also severe, unilateral and pulsating, or indistinguishable from migraine headache, occurs in half the patients, in 10% of whom it may be associated with nausea and vomiting.
Circadian distribution: Visual seizures are predominantly diurnal and can occur at any time of the day. Longer seizures, with or without hemi or generalised convulsions, tend to occur either during sleep, causing the patient to wake up, or after awakening. Thus, some children may have numerous diurnal visual seizures and only a few seizures that are exclusively nocturnal or occur on awakening.
Frequency of seizures: If untreated, patients experience frequent and brief visual seizures (often several every day or weekly). However, propagation to other seizure manifestations, such as focal or generalised convulsions, is much less frequent.
Juvenile myoclonic epilepsy (JME) is an idiopathic generalized epilepsy that occurs in patients aged 8 to 20 years. Patients have normal cognition and are otherwise neurologically intact. The most common seizure is myoclonic jerks, although generalized tonic-clonic seizures and absence seizures may occur as well. Myoclonic jerks usually cluster in the early morning after awakening. The EEG reveals generalized 4–6 Hz spike wave discharges or multiple spike discharges. These patients are often first diagnosed when they have their first generalized tonic-clonic seizure later in life, when they experience sleep deprivation (e.g., freshman year in college after staying up late to study for exams). Alcohol withdrawal can also be a major contributing factor in breakthrough seizures, as well. The risk of the tendency to have seizures is lifelong; however, the majority have well-controlled seizures with anticonvulsant medication and avoidance of seizure precipitants.
Frontal lobe epilepsy, usually a symptomatic or cryptogenic localization-related epilepsy, arises from lesions causing seizures that occur in the frontal lobes of the brain. These epilepsies can be difficult to diagnose because the symptoms of seizures can easily be confused with nonepileptic spells and, because of limitations of the EEG, be difficult to "see" with standard scalp EEG.
Juvenile absence epilepsy is an idiopathic generalized epilepsy with later onset than CAE, typically in prepubertal adolescence, with the most frequent seizure type being absence seizures. Generalized tonic-clonic seizures can occur. Often, 3 Hz spike-wave or multiple spike discharges can be seen on EEG. The prognosis is mixed, with some patients going on to a syndrome that is poorly distinguishable from JME.
The main sign of a gelastic seizure is a sudden outburst of laughter or crying with no apparent cause. The laughter may sound unpleasant and sardonic rather than joyful. The outburst usually lasts for less than a minute. During or shortly after a seizure, an individual might display some twitching, strange eye movements, lip smacking, fidgeting or mumbling. If a person who suffers from the seizures is hooked up to an electroencephalogram it will reveal interictal epileptic discharges. This syndrome usually manifests itself before the individual reaches the age of three or four. The temporal lobes, and the hypothalamus are the areas of the brain with the most involvement with these seizures. This may cause learning disabilities, and faulted cognitive function as well. It is not uncommon for children to have tonic-clonic seizures, and atonic seizures directly following the seizure. Those that are associated with hypothalamic hamartomas may occur as often as several times hourly and typically begin during infancy. Seizures that occur in infancy may include bursts of cooing, respirations, giggling, and smiling. Due to early hypothalamic-pituitary-gonadal axis activation in girls who suffer from the seizures, it is not uncommon for them to display secondary sex characteristics before the age of eight.
A gelastic seizure is typically caused by a hypothalamic hamartoma, or a brain tumor. A hypothalamic hamartoma is defined as a benign mass of glial tissue on or near the hypothalamus. The size of the hamartoma can vary from one centimeter to larger than three centimeters. They can cause several different types of seizures including a Gelastic Seizure. These structures can be detected with different imaging modalities such as computed tomography and magnetic resonance imaging. A computed tomography scan of an individual with a hypothalamic hamartoma would reveal an suprasellar mass with the same density as brain tissue. Images of these masses are not enhanced with the use of contrast. However, although a computed tomography scan may be useful in diagnosing the cause of a seizure, in the case of a hypothalamic hamartoma, magnetic resonance imaging is the tool of choice due to the cerebrospinal fluid which defines these masses. Photon emission computed tomography may also be used. This involves the use of a radiotracer which is taken up by the ictal region of the brain which is typically where the tumor lies. Gelastic seizures have been observed after taking a birth control pill (Maxim (R)).
Optic nerve hypoplasia is the only reported condition with gelastic seizures without hypothalamic hamartomas, suggesting that hypothalamic disorganization alone can cause gelastic seizures.
The cardinal features of Rolandic epilepsy are infrequent, often single, focal seizures consisting of:
Hemifacial sensorimotor seizures are often entirely localised in the lower lip or spread to the ipsilateral hand. Motor manifestations are sudden, continuous or bursts of clonic contractions, usually lasting from a few seconds to a minute. Ipsilateral tonic deviation of the mouth is also common. Hemifacial sensory symptoms consist of unilateral numbness mainly in the corner of the mouth.
Hemifacial seizures are often associated with an inability to speak and hypersalivation:
"The left side of my mouth felt numb and started jerking and pulling to the left, and I could not speak to say what was happening to me."
Negative myoclonus can be observed in some cases, as an interruption of tonic muscular activity
Oropharyngolaryngeal ictal manifestations are unilateral sensorimotor symptoms inside the mouth. Numbness, and more commonly paraesthesias (tingling, prickling, freezing), are usually diffuse on one side or, exceptionally, may be highly localised even to one tooth. Motor oropharyngolaryngeal symptoms produce strange sounds, such as death rattle, gargling, grunting and guttural sounds, and combinations:
"In his sleep, he was making guttural noises, with his mouth pulled to the right, ‘as if he was chewing his tongue’". "We heard her making strange noises ‘like roaring’ and found her unresponsive, head raised from the pillow, eyes wide open, rivers of saliva coming out of her mouth, rigid."
Arrest of speech is a form of anarthria. The child is unable to utter a single intelligible word and attempts to communicate with gestures.
"My mouth opened and I could not speak. I wanted to say I cannot speak. At the same time, it was as if somebody was strangling me."
Hypersalivation , a prominent autonomic manifestation, is often associated with hemifacial seizures, oro-pharyngo-laryngeal symptoms and speech arrest. Hypersalivation is not just frothing:
"Suddenly my mouth is full of saliva, it runs out like a river and I cannot speak."
Syncope-like epileptic seizures may occur, probably as a concurrent symptom of Panayiotopoulos syndrome:
"She lies there, unconscious with no movements, no convulsions, like a wax work, no life."
Consciousness and recollection are fully retained in more than half (58%) of Rolandic seizures.
"I felt that air was forced into my mouth, I could not speak and I could not close my mouth. I could understand well everything said to me. Other times I feel that there is food in my mouth and there is also a lot of salivation. I cannot speak."
In the remainder (42%), consciousness becomes impaired during the ictal progress and in one third there is no recollection of ictal events.
Progression to hemiconvulsions or generalised tonic–clonic seizures occurs in around half of children and hemiconvulsions may be followed by postictal Todd’s hemiparesis .
Duration and circadian distribution: Rolandic seizures are usually brief, lasting for 1–3 min. Three quarters of seizures occur during nonrapid eye movement sleep, mainly at sleep onset or just before awakening.
Status epilepticus: Although rare, focal motor status or hemiconvulsive status epilepticus is more likely to occur than secondarily generalised convulsive status epilepticus, which is exceptional. Opercular status epilepticus usually occurs in children with atypical evolution or may be induced by carbamazepine or lamotrigine. This state lasts for hours to months and consists of ongoing unilateral or bilateral contractions of the mouth, tongue or eyelids, positive or negative subtle perioral or other myoclonus, dysarthria, speech arrest, difficulties in swallowing, buccofacial apraxia and hypersalivation. These are often associated with continuous spikes and waves on an EEG during NREM sleep.
Other seizure types: Despite prominent hypersalivation, focal seizures with primarily autonomic manifestations (autonomic seizures) are not considered part of the core clinical syndrome of Rolandic epilepsy. However, some children may present with independent autonomic seizures or seizures with mixed Rolandic-autonomic manifestations including emesis as in Panayiotopoulos syndrome.
Atypical forms: Rolandic epilepsy may present with atypical manifestations such early age at onset, developmental delay or learning difficulties at inclusion, other seizure types, atypical EEG abnormalities.
These children usually have normal intelligence and development. Learning can remain unimpaired while a child is afflicted with Rolandic epilepsy.
Tonic–clonic Seizures with repetitive sequences of stiffening and jerking of the extremities.
Myoclonic Seizures with rapid, brief contractions of muscles.
Atonic Seizures with a sudden loss of muscle tone, often resulting in sudden collapse. These are also called drop seizures.
Absence A generalized seizure characterized by staring off and occasionally some orofacial automatisms.
Myoclonic astatic Seizures that involve a myoclonic seizure followed immediately by an atonic seizure. This type of seizure is exclusive to MAE and is one of the defining characteristics of this syndrome.
Tonic Muscle stiffening or rigidity. This seizure is rare in this syndrome.
There are six main types of generalized seizures: tonic-clonic, tonic, clonic, myoclonic, absence, and atonic seizures. They all involve a loss of consciousness and typically happen without warning.
- Tonic-clonic seizures present with a contraction of the limbs followed by their extension, along with arching of the back for 10–30 seconds. A cry may be heard due to contraction of the chest muscles. The limbs then begin to shake in unison. After the shaking has stopped it may take 10–30 minutes for the person to return to normal.
- Tonic seizures produce constant contractions of the muscles. The person may turn blue if breathing is impaired.
- Clonic seizures involve shaking of the limbs in unison.
- Myoclonic seizures involve spasms of muscles in either a few areas or generalized through the body.
- Absence seizures can be subtle, with only a slight turn of the head or eye blinking. The person often does not fall over and may return to normal right after the seizure ends, though there may also be a period of post-ictal disorientation.
- Atonic seizures involve the loss of muscle activity for greater than one second. This typically occurs bilaterally (on both sides of the body).
Focal seizures are often preceded by certain experiences, known as an aura. These may include: sensory, visual, psychic, autonomic, olfactory or motor phenomena.
In a complex partial seizure a person may appear confused or dazed and can not respond to questions or direction. Focal seizure may become generalized.
Jerking activity may start in a specific muscle group and spread to surrounding muscle groups—known as a "Jacksonian march". Unusual activities that are not consciously created may occur. These are known as automatisms and include simple activities like smacking of the lips or more complex activities such as attempts to pick something up.
Epileptic symptoms are frequently the product of the spread of overactivation occurring within one central foci that travels to lateral brain regions thereby causing an array of symptoms. Due to the massive amount of diversity in both the cognitive and motor functions that occur within the frontal lobes, there is an immense variety in the types of symptoms that can arise from epileptic seizures based on the side and topography of the focal origin. In general these symptoms can range anywhere from asymmetric and abnormal body positioning to repetitive vocal outbursts and repetitive jerking movements. The symptoms typically come in short bursts that last less than a minute and often occur while a patient is sleeping. In most cases, a patient will experience a physical or emotional Aura of tingling, numbness or tension prior to a seizure occurring. Fear is associated with temporal and frontal lobe epilepsies, but in FLE the fear is predominantly expressed on the person's face whereas in TLE the fear is subjective and internal, not perceptible to the observer.
Tonic posture and clonic movements are common symptoms among most of the areas of the frontal lobe, therefore the type of seizures associated with frontal lobe epilepsy are commonly called tonic-clonic seizures. Dystonic motor movements are common to both TLE and FLE, but are usually the first symptom in FLE episodes where they are quite brief and do not affect consciousness. The seizures are complex partial, simple partial, secondarily generalized or a combination of the three. These partial seizures are often misdiagnosed as psychogenic seizures. A wide range of more specific symptoms arise when different parts of the frontal cortex are affected.
- Supplementary motor area (SMA)
- The onset and relief of the seizure are quite abrupt.
- The tonic posturing in this area is unilateral or asymmetric between the left and right hemispheres. A somatosensory aura frequently precedes many large motor and vocal symptoms and most often the afflicted person is responsive.
- "Motor symptoms": Facial grimacing and complex automatisms like kicking and pelvic thrusting
- "Vocal symptoms": Laughing, yelling, or speech arrest.
- Primary motor cortex
- The primary motor cortex has jacksonian seizures that spread to adjacent areas of the lobe which often trigger a second round of seizures originating in another cortical area. The seizures are much simpler than those that originate in the SMA and are usually clonic or myoclonic movements with speech arrest. Some dystonic or contralateral adversive posturing may also be present.
- Medial frontal, cingulate gyrus, orbitofrontal, or frontopolar regions
- Motor symptoms of seizures in this area are accompanied by emotional feelings and viscerosensory symptoms. Motor and vocal agitation are similar to that of the SMA with short repetitive thrashing, pedaling, thrusting, laughing, screaming and/or crying.
- This is some of what can cause the misdiagnosis of a psychological disorder.
- Dorsolateral cortex
- This area does not seem to have many motor symptoms beyond tonic posturing or clonic movements. Contralateral or less commonly ipsilateral head turn and eye deviation are commonly associated with this area as well.
- Operculum
- Many of the symptoms associated with this area involve the head and digestive tract: swallowing, salivation, mastication and possibly gustatory hallucinations. Preceding the seizure the person is fearful and often has an epigastric aura. There is not much physical movement except clonic facial movements. Speech is often arrested.
"Focal aware" means that the level of consciousness is not altered during the seizure. In temporal lobe epilepsy, a focal seizure usually causes abnormal sensations only.
These may be:
- Sensations such as déjà vu (a feeling of familiarity), jamais vu (a feeling of unfamiliarity)
- Amnesia; or a single memory or set of memories
- A sudden sense of unprovoked fear and anxiety
- Nausea
- Auditory, visual, olfactory, gustatory, or tactile hallucinations.
- Visual distortions such as macropsia and micropsia
- Dissociation or derealisation
- Synesthesia (stimulation of one sense experienced in a second sense) may transpire.
- Dysphoric or euphoric feelings, fear, anger, and other emotions may also occur. Often, the patient cannot describe the sensations.
Olfactory hallucinations often seem indescribable to patients beyond "pleasant" or "unpleasant".
Focal aware seizures are often called "auras" when they serve as a warning sign of a subsequent seizure. Regardless an "aura" is actually a seizure itself, and such a focal seizure may or may not progress to a focal impaired awareness seizure. People who only experience focal aware seizures may not recognize what they are, nor seek medical care.
The most common symptom of abdominal epilepsy is abdominal pain followed by uncontrollable vomiting, usually preceded by lethargy. Symptoms also include generalized tonic-clonic seizures followed by sleep, confusion, and unresponsiveness.
The most frequently reported symptoms are elementary "visual hallucinations" characterized by basic irritations to perception of sight. Scotomas and aumarosis also occur and are predictors of poor medication response Hallucinations may be described as flashing small circular patterns or zigzags. Vomiting or temporary blindness may occur and visual seizures may be followed by a headache leading to a frequent misdiagnosis as migraine. Seizures may become generalized.
The most common type (60%) of seizures are convulsive. Of these, one-third begin as generalized seizures from the start, affecting both hemispheres of the brain. Two-thirds begin as focal seizures (which affect one hemisphere of the brain) which may then progress to generalized seizures. The remaining 40% of seizures are non-convulsive. An example of this type is the absence seizure, which presents as a decreased level of consciousness and usually lasts about 10 seconds.
Focal seizures are often preceded by certain experiences, known as auras. They include sensory (visual, hearing, or smell), psychic, autonomic, and motor phenomena. Jerking activity may start in a specific muscle group and spread to surrounding muscle groups in which case it is known as a Jacksonian march. Automatisms may occur, which are non-consciously-generated activities and mostly simple repetitive movements like smacking of the lips or more complex activities such as attempts to pick up something.
There are six main types of generalized seizures: tonic-clonic, tonic, clonic, myoclonic, absence, and atonic seizures. They all involve loss of consciousness and typically happen without warning.
Tonic-clonic seizures occur with a contraction of the limbs followed by their extension along with arching of the back which lasts 10–30 seconds (the tonic phase). A cry may be heard due to contraction of the chest muscles, followed by a shaking of the limbs in unison (clonic phase). Tonic seizures produce constant contractions of the muscles. A person often turns blue as breathing is stopped. In clonic seizures there is shaking of the limbs in unison. After the shaking has stopped it may take 10–30 minutes for the person to return to normal; this period is called the "postictal state" or "postictal phase." Loss of bowel or bladder control may occur during a seizure. The tongue may be bitten at either the tip or on the sides during a seizure. In tonic-clonic seizure, bites to the sides are more common. Tongue bites are also relatively common in psychogenic non-epileptic seizures.
Myoclonic seizures involve spasms of muscles in either a few areas or all over. Absence seizures can be subtle with only a slight turn of the head or eye blinking. The person does not fall over and returns to normal right after it ends. Atonic seizures involve the loss of muscle activity for greater than one second. This typically occurs on both sides of the body.
About 6% of those with epilepsy have seizures that are often triggered by specific events and are known as reflex seizures. Those with reflex epilepsy have seizures that are only triggered by specific stimuli. Common triggers include flashing lights and sudden noises. In certain types of epilepsy, seizures happen more often during sleep, and in other types they occur almost only when sleeping.
Focal impaired awareness seizures are seizures which impair consciousness to some extent: they alter the person's ability to interact normally with their environment. They usually begin with a focal aware seizure, then spread to a larger portion of the temporal lobe, resulting in impaired consciousness. They may include autonomic and psychic features present in focal aware seizures.
Signs may include:
- Motionless staring
- Automatic movements of the hands or mouth
- Confusion and disorientation
- Altered ability to respond to others, unusual speech
- Transient aphasia (losing ability to speak, read, or comprehend spoken word)
These seizures tend to have a warning or aura before they occur, and when they occur they generally tend to last only 1–2 minutes. It is not uncommon for an individual to be tired or confused for up to 15 minutes after a seizure has occurred, although postictal confusion can last for hours or even days. Though they may not seem harmful, due to the fact that the individual does not normally seize, they can be extremely harmful if the individual is left alone around dangerous objects. For example, if a person with complex partial seizures is driving alone, this can cause them to run into the ditch, or worse, cause an accident involving multiple people. With this type, some people do not even realize they are having a seizure and most of the time their memory from right before or after the seizure is wiped. First-aid is only required if there has been an injury or if this is the first time a person has had a seizure.
The onset of seizures is between the ages of 2 and 5. EEG shows regular and irregular bilaterally synchronous 2- to 3-Hz spike-waves and polyspike patterns with a 4- to 7-Hz background. 84% of affected children show normal development prior to seizures; the remainder show moderate psychomotor retardation mainly affecting speech. Boys (74%) are more often affected than girls (Doose and Baier 1987a).
Possible causes include:
- Syncope (fainting)
- Reflex anoxic seizures
- Breath-holding spells of childhood
- Hypoglycaemia
- Cataplexy
- Hyperekplexia, also called startle syndrome
- Migraine
- Narcolepsy
- Non-epileptic myoclonus
- Opsoclonus
- Parasomnias, including night terrors
- Paroxysmal kinesigenic dyskinesia
- Repetitive or ritualistic behaviours
- Tics
- AADC Deficiency
Episodes that include complex hyperactivity of the proximal portions of the limbs that lead to increased overall motor activity are called hypermotor seizures. When associated with bizarre movements and vocalizations these seizures are often misdiagnosed as pseudoseizures or other episodic movement disorders such as psychogenic movement disorders, familial paroxysmal dystonic choreoathetosis, paroxysmal kinesogenic choreoathetosis, or episodic ataxia type 1. Hypermotor seizure in children are often confused with pavor nocturnus (night terrors). Paroxysmal nocturnal dystonia or hypnogenic paroxysmal dystonia are other names given to describe FLE symptoms but are simply just FLE.
Autosomal Dominant Nocturnal Frontal Lobe Epilepsy (ADNFLE) is the best understood form of frontal lobe epilepsy but is often misdiagnosed as sleep apnea. Both disorders are characterized by awakening during the night which leads to daytime sleepiness. Some symptoms of sleep apnea overlap with those of ADNFLE, such as sudden awakening accompanied by a feeling of choking and on occasion motor activity which makes diagnosis difficult based on symptoms alone. Video surveillance as well as EEG is occasionally needed to differentiate between the two disorders. It has been reported that sleep apnea might be associated with epilepsy which would account for some of the misdiagnoses.
Myoclonus can be described as brief jerks of the body; it can involve any part of the body, but it is mostly seen in limbs or facial muscles. The jerks are usually involuntary and can lead to falls. EEG is used to read brain wave activity. Spike activity produced from the brain is usually correlated with brief jerks seen on EMG or excessive muscle artifact. They usually occur without detectable loss of consciousness and may be generalized, regional or focal on the EEG tracing. Myclonus jerks can be epileptic or not epileptic. Epileptic myoclonus is an elementary electroclinical manifestation of epilepsy involving descending neurons, whose spatial (spread) or temporal (self-sustained repetition) amplification can trigger overt epileptic activity.
Prognosis is generally good, and seizures usually respond to classic antiepileptics Resection of pathological tissue has been used successfully to treat occipital lobe epilepsy.
The signs of vertiginous epilepsy often occur without a change in the subject’s consciousness so that they are still aware while experiencing the symptoms. It is often described as a sudden onset of feeling like one is turning in one direction, typically lasting several seconds. Although subjects are aware during an episode, they often cannot remember specific details due to disorientation, discomfort, and/or partial cognitive impairment. This sensation of rotational movement in the visual and auditory planes is also known as a vertiginous aura (symptom), which can precede a seizure or may constitute a seizure itself. Auras are a “portion of the seizure that occur before consciousness is lost and for which memory is retained afterwards.” Auras can be focused in different regions of the brain and can thus affect different functions. Some such symptoms that may accompany vertiginous epilepsy include:
- Auditory hallucination
- Cognitive impairment
- Motor activity
- Ictal behavior
- Limbic auras
Many people tend to mistake dizziness as vertigo, and although they sound similar, dizziness is not considered a symptom of vertiginous epilepsy. Dizziness is the sensation of imbalance or floating, impending loss of consciousness, and/or confusion. This is different from vertigo which is characterized by the illusion of rotational movement caused by the “conflict between the signals sent to the brain by balance- and position-sensing systems of the body”.
The International League Against Epilepsy (ILAE) define an epileptic seizure as "a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain." Epileptic seizures can occur in someone who does not have epilepsy – as a consequence of head injury, drug overdose, toxins, eclampsia or febrile convulsions, for example.
Medically, when used on its own, the term seizure implies an epileptic seizure. The lay use of this word can also include sudden attacks of illness, loss of control, spasm or stroke. Where the physician is uncertain as to the diagnosis, the medical term paroxysmal event and the lay terms spells, funny turns or attacks may be used.
After the active portion of a seizure (the ictal state) there is typically a period of recovery during which there is confusion, referred to as the postictal period before a normal level of consciousness returns. It usually lasts 3 to 15 minutes but may last for hours. Other common symptoms include feeling tired, headache, difficulty speaking, and abnormal behavior. Psychosis after a seizure is relatively common, occurring in 6–10% of people. Often people do not remember what happened during this time. Localized weakness, known as Todd's paralysis, may also occur after a focal seizure. When it occurs it typically lasts for seconds to minutes but may rarely last for a day or two.
Myoclonic jerks that are not epileptic may be due to a nervous system disorder or other metabolic abnormalities that may arise in renal (e.g. hyperuraemia) and liver failure (e.g. high ammonia states).
Epilepsy is most commonly recognised by involuntary movements of the head and limbs, however other characteristics include salivation, lack of and anxiety. Animals often lose consciousness and are not aware of their surroundings.