Convulsion

Epilepsy is a neuronal disorder with multifactorial manifestations.[7] It is a noncontagious illness and is usually associated with sudden attacks[8] of seizures, which are an immediate and initial anomaly in the electrical activity of the brain that disrupts part or all of the body.[7] Various areas of the brain can be disturbed by epileptic events.[9] Epileptic seizures can have contrary clinical features.[7] Epileptic seizures can have long-lasting effects on cerebral blood flow.[10]

Various kinds of epileptic seizures affect 60 million people worldwide.[8]

The most common type of seizure is called a generalized seizure, also known as a generalized convulsion. This is characterized by a loss of consciousness which may lead to the person collapsing. The body stiffens for about a minute and then jerks uncontrollably for the next minute. During this, the patient may fall and injure themselves or bite their tongue, their eyes roll back, and lose control of their bladder. A familial history of seizures puts a person at a greater risk of developing them.[11][12] Generalized seizures have been broadly classified into two categories: motor and non-motor. [7]

A generalized tonic-clonic seizure (GTCS), also known as a grand mal seizure, is a whole-body seizure that has a tonic phase followed by clonic muscle retrenchments.[13][14] GTCSs can happen in people of all ages.[14] GTCSs are very hazardous, and they increase the risk of injuries and sudden unexpected death in epilepsy (SUDEP).[15] SUDEP is a sudden, unexpected, nontraumatic death in patients with epilepsy.[15] Strong convulsions that are related to GTCSs can also cause falls and severe injuries.[15]

Not all generalized seizures produce convulsions. For example, in an absence seizure, also known as a petit mal seizure, the brain experiences electrical disturbances but the body remains motionless and unresponsive.[2]

A common cause of convulsions in children is febrile seizures, a type of seizure associated with a high body temperature. This high temperature is a usual immune response to infection, and in febrile convulsions, the reason for the fever is extra-cranial (such as a body-wide viral infection).[16] In Nigeria, malaria—which can cause sudden, high fevers—is a significant cause of convulsions among children under 5 years of age.[17]

Febrile seizures fall into two categories: simple and complex.[18] A simple febrile seizure is generalized, occurs singularly, and lasts less than 15 minutes.[18] A complex febrile seizure can be focused in an area of the body, occur more than once, and lasts for more than 15 minutes.[18] Febrile seizures affect 2–4% of children in the United States and Western Europe, it is the most common childhood seizure.[18] The exact reason for febrile convulsion is unidentified, though it might be the outcome of the interchange between environmental and genetic factors.[16]

Psychogenic non-epileptic seizures (PNES) are described as neurobehavioral conditions[19] or "psychogenic illnesses" which occur not due to the electrical disturbances in a person's brain but due to mental and emotional stress.[2] PNES are an important differential diagnosis and a common occurrence in epilepsy centers.[20] According to the 5th Edison of Diagnostic and Statistical Manual of Mental Disorders (DSM 5), PNES is classified as a "conversion disorder" or Functional Neurologic Symptom Disorder characterized by alterations in behavior, motor activity, consciousness, and sensation.[21] A few neuroimaging (functional and structural) studies suggest that PNES may replicate sensorimotor alterations, emotional regulation, cognitive control, and integration of neural circuits.[22]

There is a linkage between infantile convulsion and paroxysmal dyskinesia.[23] Paroxysmal kinesigenic dyskinesia (PKD) is characterized by sudden involuntary movement caused by sudden stress or excitement.[24] The relationship between convulsion and PKD is mainly due to the common mechanism of pathophysiology.[23]