This article’s pretty interesting, about a village in Nicaragua where some 60 people are suffering for a ‘collective madness’ known as ‘grisi siknis’ in the local Miskut language.

In all cases, the patients have the same symptoms: long periods of coma-like unconsciousness, interrupted by sudden bouts of frenzied behaviour.

During the attacks, sufferers attempt to flee their communities with their eyes closed, seizing any weapon they can find with which they appear to try to defend themselves against invisible attackers.

There are teams of physicians and traditional healers who are trying to figure out how to help these people. Apparently it’s one of those syndromes that only afflicts this specific cultural group. And western doctors are more or less powerless to help these people.

I find this really interesting for some reason. They also mention another culturally-bound syndrome that it’s similar to. It’s called Pibloktoq or Arctic Hysteria and occurs among Greenland Eskimos. According to this site listing culturally-bound syndromes, Arctic hysteria is…

an abrupt dissociative episode accompanied by extreme excitement of up to 30 minutes’ duration and frequently followed by convulsive seizures and coma lasting up to 12 hours. The individual may be withdrawn or mildly irritable for a period of hours or days before the attack and will typically report complete amnesia for the attack. During the attack, the individual may tear off his or her clothing, break furniture, shout obscenities, eat feces, flee from protective shelters, or perform other irrational or dangerous acts.

I also found this page which claims that grisi siknis is similar to what in the West is called a Dissociative Fugue State