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Seizure
A seizure is a sudden, brief disruption of brain activity caused by abnormal, excessive, or synchronous neuronal firing. Depending on the regions of the brain involved, seizures can lead to changes in movement, sensation, behavior, awareness, or consciousness. Symptoms vary widely. Some seizures involve subtle changes, such as brief lapses in attention or awareness (as seen in absence seizures), while others cause generalized convulsions with loss of consciousness ( tonic–clonic seizures). Most seizures last less than two minutes and are followed by a postictal period of confusion, fatigue, or other symptoms. A seizure lasting longer than five minutes is a medical emergency known as status epilepticus. Seizures are classified as provoked, when triggered by a known cause such as fever, head trauma, or metabolic imbalance, or unprovoked, when no immediate trigger is identified. Recurrent unprovoked seizures define the neurological condition epilepsy. Clinical features Seizur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epilepsy
Epilepsy is a group of Non-communicable disease, non-communicable Neurological disorder, neurological disorders characterized by a tendency for recurrent, unprovoked Seizure, seizures. A seizure is a sudden burst of abnormal electrical activity in the brain that can cause a variety of symptoms, ranging from brief lapses of awareness or muscle jerks to prolonged convulsions. These episodes can result in physical injuries, either directly, such as broken bones, or through causing accidents. The diagnosis of epilepsy typically requires at least two unprovoked seizures occurring more than 24 hours apart. In some cases, however, it may be diagnosed after a single unprovoked seizure if clinical evidence suggests a high risk of recurrence. Isolated seizures that occur without recurrence risk or are provoked by identifiable causes are not considered indicative of epilepsy. The underlying cause is often unknown, but epilepsy can result from brain injury, stroke, infections, Brain tumor, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Absence Seizures
Absence seizures are one of several kinds of generalized seizures. Absence seizures are characterized by a brief loss and return of consciousness, generally not followed by a period of lethargy (i.e. without a notable postictal state). Absence seizures are most common in children. They affect both sides of the brain. In the past, absence epilepsy was referred to as "pyknolepsy," a term derived from the Greek word "pyknos," signifying "extremely frequent" or "grouped". These seizures are sometimes referred to as petit mal seizures (from the French for "little illness", a term dated to the late 18th century); however, usage of this terminology is no longer recommended. Childhood absence epilepsy represents a significant portion, accounting for approximately 10 to 17%, of all cases of childhood-onset epilepsy, establishing it as the most common form of pediatric epilepsy. This syndrome is characterized by daily occurrences of frequent but brief episodes of staring spells. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Psychogenic Seizure
Psychogenic non-epileptic seizures (PNES), also referred to as functional seizures or dissociative seizures, are episodes that resemble epileptic seizures but are not caused by abnormal electrical activity in the brain. Instead, they are classified as a type of functional neurological disorder (FND), in which symptoms arise from changes in brain function rather than structural disease or epilepsy. During a PNES episode, seizure-like behavior occurs in the absence of epileptiform activity on electroencephalogram (EEG). PNES can be difficult to distinguish from epileptic seizures based on clinical observation alone. Diagnosis is typically confirmed through video-EEG monitoring, which records both the clinical event and the absence of epileptiform activity. These episodes are involuntary and genuine, not consciously produced. Management primarily involves psychological treatment, particularly cognitive behavioral therapy (CBT). Outcomes vary and are influenced by factors such as e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Postictal State
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. The ictal period is the seizure itself; the interictal period is the time between seizures, when brain activity is more normal; and the preictal period is the time leading up to a seizure: * ''Ictal period'' refers to a physiologic state or event such as a seizure, stroke, or headache. The word originates from the Latin word ''ictus'', meaning a blow or a stroke. In electroencephalography (EEG), the recording during a seizure is said to be "ictal". The following definitions refer to the temporal relation with seizures. * ''Pre-ictal'' refers to the state immediately before the actual seizure, stroke, or headache. * ''Post-ictal'' refers to the state shortly after th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Status Epilepticus
Status epilepticus (SE), or status seizure, is a medical condition with abnormally prolonged seizures. It can have long-term consequences, manifesting as a single seizure lasting more than a defined time (time point 1), or 2 or more seizures over the same period without the person returning to normal between them. The seizures can be of the Generalized tonic–clonic seizure, tonic–clonic type, with a regular pattern of contraction and extension of the arms and legs, also known as convulsive status epilepticus, or of types that do not involve contractions, such as absence seizures or complex partial seizures. Convulsive status epilepticus is a life-threatening medical emergency, particularly if treatment is delayed. For convulsive status epilepticus, the most dangerous type, 5 minutes is the time point at which the seizure or seizures would be considered status epilepticus, so this is defined as a convulsion lasting more than 5 minutes, or two convulsions within 5 minutes without ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electroencephalogram
Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The bio signals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex and allocortex. It is typically non-invasive, with the EEG electrodes placed along the scalp (commonly called "scalp EEG") using the International 10–20 system, or variations of it. Electrocorticography, involving surgical placement of electrodes, is sometimes called "intracranial EEG". Clinical interpretation of EEG recordings is most often performed by visual inspection of the tracing or quantitative EEG analysis. Voltage fluctuations measured by the EEG bio amplifier and electrodes allow the evaluation of normal brain activity. As the electrical activity monitored by EEG originates in neurons in the underlying brain tissue, the recordings made by the electrodes on the surface of the scalp vary in accordance with their orie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electroencephalography
Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignal, bio signals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex and allocortex. It is typically non-invasive, with the EEG electrodes placed along the scalp (commonly called "scalp EEG") using the 10–20 system (EEG), International 10–20 system, or variations of it. Electrocorticography, involving surgical placement of electrodes, is sometimes called Electrocorticography, "intracranial EEG". Clinical interpretation of EEG recordings is most often performed by visual inspection of the tracing or quantitative EEG, quantitative EEG analysis. Voltage fluctuations measured by the EEG bioamplifier, bio amplifier and electrodes allow the evaluation of normal Brain activity and meditation, brain activity. As the electrical activity monitored by EEG originates in neurons in the underlying Huma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alcohol Withdrawal
Alcohol withdrawal syndrome (AWS) is a set of symptoms that can occur following a reduction in or cessation of alcohol use after a period of excessive use. Symptoms typically include anxiety, shakiness, sweating, vomiting, fast heart rate, and a mild fever. More severe symptoms may include seizures, and delirium tremens (DTs); which can be fatal in untreated patients. Symptoms start at around 6 hours after the last drink. Peak incidence of seizures occurs at 24 to 36 hours and peak incidence of delirium tremens is at 48 to 72 hours. Alcohol withdrawal may occur in those who are alcohol dependent. This may occur following a planned or unplanned decrease in alcohol intake. The underlying mechanism involves a decreased responsiveness of GABA receptors in the brain. The withdrawal process is typically followed using the Clinical Institute Withdrawal Assessment for Alcohol scale (CIWA-Ar). The typical treatment of alcohol withdrawal is with benzodiazepines such as chlordiazep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Migraine Aura
An aura is a perceptual disturbance experienced by some with epilepsy or migraine. An epileptic aura is actually a minor seizure. Epileptic and migraine auras are due to the involvement of specific areas of the brain, which are those that determine the symptoms of the aura. Therefore, if the visual area is affected, the aura will consist of visual symptoms, while if a sensory one, then sensory symptoms will occur. Epileptic auras are subjective sensory or psychic phenomena due to a focal seizure, i.e. a seizure that originates from that area of the brain responsible for the function which then expresses itself with the symptoms of the aura. It is important because it makes it clear where the alteration causing the seizure is located. An epileptic aura is in most cases followed by other manifestations of a seizure, for example a convulsion, since the epileptic discharge spreads to other parts of the brain. Rarely it remains isolated. Auras, when they occur, allow some people who h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syncope (medicine)
Syncope , commonly known as fainting or passing out, is a loss of consciousness and muscle strength characterized by a fast onset, short duration, and spontaneous recovery. It is caused by a decrease in blood flow to the brain, typically from low blood pressure. There are sometimes symptoms before the loss of consciousness such as lightheadedness, sweating, pale skin, blurred vision, nausea, vomiting, or feeling warm. Syncope may also be associated with a short episode of muscle twitching. Psychiatric causes can also be determined when a patient experiences fear, anxiety, or panic; particularly before a stressful event, usually medical in nature. When consciousness and muscle strength are not completely lost, it is called presyncope. It is recommended that presyncope be treated the same as syncope. Causes range from non-serious to potentially fatal. There are three broad categories of causes: heart or blood vessel related; reflex, also known as neurally mediated; and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traumatic Brain Injury
A traumatic brain injury (TBI), also known as an intracranial injury, is an injury to the brain caused by an external force. TBI can be classified based on severity ranging from mild traumatic brain injury (mTBI/concussion) to severe traumatic brain injury. TBI can also be characterized based on mechanism (closed head injury, closed or penetrating head injury) or other features (e.g., occurring in a specific location or over a widespread area). Head injury is a broader category that may involve damage to other structures such as the scalp and skull. TBI can result in physical, cognitive, social, emotional and behavioral symptoms, and outcomes can range from complete recovery to permanent disability or death. Causes include Falling (accident), falls, vehicle collisions, and violence. Brain trauma occurs as a consequence of a sudden acceleration or deceleration of the brain within the skull or by a complex combination of both movement and sudden impact. In addition to the damage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Oscillation
Neural oscillations, or brainwaves, are rhythmic or repetitive patterns of neural activity in the central nervous system. Neural tissue can generate oscillatory activity in many ways, driven either by mechanisms within individual neurons or by interactions between neurons. In individual neurons, oscillations can appear either as oscillations in membrane potential or as rhythmic patterns of action potentials, which then produce oscillatory activation of post-synaptic neurons. At the level of neural ensembles, synchronized activity of large numbers of neurons can give rise to macroscopic oscillations, which can be observed in an electroencephalogram. Oscillatory activity in groups of neurons generally arises from feedback connections between the neurons that result in the synchronization of their firing patterns. The interaction between neurons can give rise to oscillations at a different frequency than the firing frequency of individual neurons. A well-known example of macros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
