Does this condition actually exist?

[visceral_instinct]

A while ago I read Skull Session by Daniel Hecht, about a serial killer who has a condition called hyperkinesis/hyperdynamism which makes her inhumanly strong. The novel says that the berserkers of Norse mythology actually existed and they had this condition. Apparently it causes a seizurelike activity in the hypothalamus causing massive release of adrenaline and other fight or flight chemicals, and that's how they got their superhuman strength.

Does this condition actually exist or was it just a really cool piece of fiction?

 

[maxg]

Hyperkinesis is a symptom that may be caused by a couple different disorders, the best known of which is attention deficit hyperactivity disorder (AD/HD), which affects a large number of children and some adults. There are other disorders that don't involve a psychological component (as AD/HD does) that cause hyperkinesis but I've not heard of any that result in excessive strength.