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Frontal lobe epilepsy, or FLE, is a neurological disorder that is characterized by brief, recurring seizures that arise in the frontal lobes of the brain, often while the patient is sleeping. It is the second most common type of epilepsy after temporal lobe epilepsy (TLE), and is related to the temporal form by the fact that both forms are characterized by the occurrence of partial (focal) seizures. Partial seizures occurring in the frontal lobes can occur in one of two different forms: either simple partial seizures (that do not affect awareness or memory) or complex partial seizures (that affect awareness or memory either before, during or after a seizure). The symptoms and clinical manifestations of frontal lobe epilepsy can differ depending on which specific area of the frontal lobe is affected. The onset of a seizure may be hard to detect since the frontal lobes contain and regulate many structures and functions about which relatively little is known. Due to the lack of knowledge surrounding the functions associated with the frontal lobes, seizures occurring in these regions of the brain may produce unusual symptoms which can often be misdiagnosed as a psychiatric disorder, non-epileptic seizure or a sleep disorder. During the onset of a seizure, the patient may exhibit abnormal body posturing, sensorimotor tics, or other abnormalities in motor skills.〔 In rare cases, uncontrollable laughing or crying may occur during a seizure.〔 Afflicted persons may or may not be aware that they are behaving in an abnormal manner, depending on the patient and type of seizure. A brief period of confusion known as a postictal state may sometimes follow a seizure occurring in the frontal lobes. However, these postictal states are often undetectable and generally do not last as long as the periods of confusion following seizures that occur in the temporal lobes. There are many different causes of frontal lobe epilepsy ranging from genetics to head trauma that result in lesions in the frontal lobes. Although frontal lobe epilepsy is often misdiagnosed, tests such as prolonged EEG monitoring and/or a MRI scan of the frontal lobes can be administered in order to reveal the presence of a tumor or vascular malformation. Unlike most epileptic EEGs, the abnormalities in FLE EEGs precede the physical onset of the seizure and aid in localization of the seizure's origin. Medications such as anti-epileptic drugs can typically control the onset of seizures, however, if medications are ineffective the patient may undergo surgery to have focal areas of the frontal lobe removed. ==Signs and symptoms== 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 outburts 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.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Frontal lobe epilepsy」の詳細全文を読む スポンサード リンク
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