Gelastic seizure

A gelastic seizure, also known as "gelastic epilepsy" is a rare type of seizure that involves a sudden burst of energy, usually in the form of laughing or crying. This syndrome usually occurs for no obvious reason and is uncontrollable. It is slightly more common in males than females. The term Gelastic originates from the Greek word "Gelos" which means laughter. This syndrome can go for very long periods of time without a diagnosis, as it may appear to be much like normal laughing or crying, if it occurs infrequently. It has been associated with several different conditions such as temporal and frontal lobe lesions, tumors, atrophy, tuberous sclerosis, hemangiomas, and post infectious foci, but mainly hypothalamic hamartomas.

The main sign of a gelastic seizure is a sudden outburst of laughter or crying with no apparent cause. The laughter may sound unpleasant and sardonic rather than joyful. The outburst usually lasts for less than a minute. During or shortly after a seizure, an individual might display some twitching, strange eye movements, lip smacking, fidgeting or mumbling. If a person who suffers from the seizures is hooked up to an electroencephalogram it will reveal interictal epileptic discharges. This syndrome usually manifests itself before the individual reaches the age of three or four. The temporal lobes, and the hypothalamus are the areas of the brain with the most involvement with these seizures. This may cause learning disabilities, and faulted cognitive function as well. It is not uncommon for children to have tonic-clonic seizures, and atonic seizures directly following the seizure. Those that are associated with hypothalamic hamartomas may occur as often as several times hourly and typically begin during infancy. Seizures that occur in infancy may include bursts of cooing, respirations, giggling, and smiling. Due to early hypothalamic-pituitary-gonadal axis activation in girls who suffer from the seizures, it is not uncommon for them to display secondary sex characteristics before the age of eight.

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