In law enforcement, an exploratory investigation of a premises or a person and the taking into custody of property or an individual in the interest of gaining evidence of unlawful activity or guilt. The latitude allowed police in carrying out searches and seizures varies greatly from country to country. In the U.S., the 4th Amendment to the Constitution prohibits unreasonable searches and seizures and requires that a warrant be issued following a finding of probable cause. The warrant must specify the place to be searched and the persons and things to be seized.
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An epileptic seizure is caused by excessive and/or hypersynchronous electrical neuronal activity, and is usually self-limiting. It can manifest as an alteration in mental state, tonic or clonic movements, convulsions, and various other psychic symptoms (such as déjà vu or jamais vu). The medical syndrome of recurrent, unprovoked seizures is termed epilepsy, but seizures can occur in people who do not have epilepsy.
The treatment of epilepsy is a subspecialty of neurology; the study of seizures is part of neuroscience. Doctors who specialize in epilepsy are epileptologists; doctors who specialize in the treatment of children with epilepsy are pediatric epileptologists.
In some cases, the full onset of a seizure event is preceded by some of the sensations described above. These sensations can serve as a warning to the sufferer that a full tonic-clonic seizure is about to occur. These "warning sensations" are cumulatively called an aura. Also, it is commonly believed among healthcare providers that many seizures, especially those in children, are preceded by tachycardia that frequently persists throughout the seizure. This early increase in heart rate may supplement an aura as a physiological warning sign of an imminent seizure.
Symptoms experienced by a person during a seizure depend on where in the brain the disturbance in electrical activity occurs. Recent studies show that seizures happen in sleep more often than was thought. A person having a tonic-clonic seizure may cry out, lose consciousness and fall to the ground, and convulse, often violently. A person having a complex partial seizure may appear confused or dazed and will not be able to respond to questions or direction. Some people have seizures that are not noticeable to others. Sometimes, the only clue that a person is having an absence seizure is rapid blinking, extreme confusion for a few seconds or sometimes into hours.
Following standardization proposal published in 1970, out-dated terms such as "petit mal", "grand mal", "Jacksonian", "psychomotor", and "temporal-lobe seizure" have fallen into disuse.
The second meta-analysis found:
The serum prolactin level is less sensitive for detecting partial seizures.
As seizures have a differential diagnosis, it is common for patients to be simultaneously investigated for cardiac and endocrine causes. Checking glucose levels, for example, is a mandatory action in the management of seizures as hypoglycemia may cause seizures, and failure to administer glucose would be harmful to the patient. Other causes typically considered are syncope and cardiac arrhythmias, and occasionally panic attacks and cataplexy. For more information, see non-epileptic seizures.
The first aid for a seizure depends on the type of seizure occurring. Generalized seizures will cause the person to fall, which may result in injury. A tonic-clonic seizure results in violent movements that cannot and should not be suppressed. The person should never be restrained, nor should there be any attempt to put something in the mouth. Potentially sharp or dangerous objects should also be moved from the vicinity, so that the individual is not hurt. After the seizure if the person is not fully conscious and alert, they should be placed in the recovery position. Bystanders should remain calm and avoid crowding the person.
It is not necessary to call an ambulance if the person is known to have epilepsy, if the seizure is shorter than five minutes and is typical for them, if it is not immediately followed by another seizure, and if the person is uninjured. Otherwise, or if in any doubt, medical assistance should be sought.
A seizure longer than five minutes is a medical emergency. Relatives and other caregivers of those known to have epilepsy often carry medicine such as rectal diazepam or buccal midazolam in order to rapidly end the seizure.
A sudden fall can lead to broken bones and other injuries. Children who are affected by frequent drop seizures may wear helmets to protect the head during a fall.
The unusual behavior resulting from the chaotic brain activity of a seizure can be misinterpreted as an aggressive act. This may invoke a hostile response or police involvement, where there was no intention to cause harm or trouble. During a prolonged seizure, the person is defenseless and may become a victim of theft.
A seizure response dog can be trained to summon help or ensure personal safety when a seizure occurs. These are not suitable for everybody. Rarely, a dog may develop the ability to sense a seizure before it occurs.
Unprovoked seizures are often associated with epilepsy and related seizure disorders.
Causes of provoked seizures include:
Some medications produce an increased risk of seizures and electroconvulsive therapy (ECT) deliberately sets out to induce a seizure for the treatment of major depression. Many seizures have unknown causes.
Seizures which are provoked are not associated with epilepsy, and people who experience such seizures are normally not diagnosed with epilepsy. However, the seizures described above resemble those of epilepsy both outwardly, and on EEG testing.
Seizures can occur after a subject witnesses a traumatic event. This type of seizure is known as a psychogenic non-epileptic seizure and is related to posttraumatic stress disorder.
Mild seizures can be induced through a combination of quickly standing, hyperventilation and applying pressure to the sternum.