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The postictal state is the altered state of consciousness after an epileptic seizure. It usually lasts between 5 and 30 minutes, but sometimes longer in the case of larger or more severe seizures, and is characterized by drowsiness, confusion, nausea, hypertension, headache or migraine, and other disorienting symptoms. Additionally, emergence from this period is often accompanied by amnesia or other memory defects. It is during this period that the brain recovers from the trauma of the seizure. While the postictal period is considered to be the period shortly after a seizure where the brain is still recovering from the seizure, the ictal period is considered to be the seizure itself, and the interictal period to be the period between seizures, when brain activity is more normal. ==Signs and symptoms== Jerome Engel defines the postictal state as “manifestations of seizure-induced reversible alterations in neuronal function but not structure.” Following a seizure it is common to experience feelings of exhaustion, both mental and physical, that can last for a day or two. Patients’ most common complaint after a seizure is an inability to think clearly, specifically “poor attention and concentration, poor short term memory, decreased verbal and interactive skills, and a variety of cognitive defects specific to individuals.” This collection of symptoms is known as the postictal state, though the word postictal means nothing more than “after the seizure”. Postictal migraines are a major complaint among epilepsy patients, and can have a variety of etiologies. One possible cause of these migraines is high intracranial pressure resulting from postictal cerebral edema. At times, patients may be unaware that they had a seizure, and the characteristic migraine is their only clue.〔 Depression is also very common after a seizure. Other symptoms associated with the postictal state are less common. Todd's paresis (TP) is a temporary regional loss of function in whatever region just experienced the seizure, and its manifestation depends on where the seizure was located. Loss of motor function is most common, and can range from weakness to full paralysis. About 6% of patients who had tonic-clonic seizures experienced TP afterward, with loss of motor function sometimes accompanied with temporary numbness, blindness, or deafness.〔 TP can also cause anterograde amnesia if the seizure included the bilateral hippocampi, and aphasia if the seizures began in the language-dominant hemisphere.〔 Symptoms typically lasts about 15 hours, but can last as long as 36 hours, and the clinician must resolve whether the loss of motor function is due to TP or ischemia.〔 Postictal psychosis (PP) is a rare but serious complication following seizures, characterized by auditory and visual hallucinations, delusions, paranoia, affective change, and aggression. Following the conclusion of the seizure, the patient feels the typical confusion and lethargy of the postictal state, and then gradually recovers to a normal state. This is called the lucid phase. In patients who experience PP, the lucid phase usually lasts between 2 hours and a week (usually more than 6 hours) before psychosis sets in. In about 12-50% of seizure patients, the lucid phase is followed by a period of psychosis that can last for 12 hours to more than 3 months (the mean is 9–10 days). This psychosis is treatable with standard antipsychotic drugs, and stops when the patient no longer experiences seizures. Postictal bliss (PB) is also reported following seizures. This has been described as a highly blissful feeling associated with the emergence from amnesia. Some of these postictal symptoms are almost always present for a period of a few hours to a day or two. In fact, confusion and lack of responsiveness after a seizure is so common and expected that if a patient doesn’t show these symptoms after a seizure, it can be a signal to clinicians that the event may not be an actual seizure at all. Usually such false seizures are instead related to syncope or have a psychogenic origin.〔 The postictal state can also be useful for the clinician when determining the focus of the seizure. Decreased verbal memory (short term) tends to result from a seizure in the dominant hemisphere, whereas seizures in the nondominant hemisphere tend to manifest with decreased visual memory. Inability to read suggests seizure foci in the language areas of the speech-dominant hemisphere, and “after a seizure semivoluntary events as mundane as nose wiping tend to be done with the hand ipsilateral to the seizure focus.”〔 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「Postictal state」の詳細全文を読む スポンサード リンク
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