Cachinnation is an excessive loud, hard, or convulsive
uncontrollable laughing for no clear reason. In
cachinnation, the mouth is wide open compared to a
normal regular laugh when it is partly open.
Cachinnation can be caused by various conditions that
damage the brain, such as severe traumatic brain
injury, poisonous bites, schizophrenia, and epilepsy.
Schizophrenia is a neurologically based mental disorder
in which one loses contact with reality, experiences
abnormal thinking, and has poor emotional
responsiveness. Epilepsy is a chronic brain condition
characterized by repeat seizures.
A seizure is an overexcitable state of nerve cells in the brain, sometimes leading to
sudden, violent, involuntary contractions of a group of muscles and/or manifestations of
decreased awareness of environmental surroundings. In social settings, cachinnation
tends to make others quite uncomfortable and as such, it can quickly and easily lead to
social alienation. While patients without neurological problems can also laugh loudly and
uncontrollably, there is typically a clear reason for this unlike in neurologically-based
cachinnation. In severe cases, cachinnation can actually be physically dangerous
because it can cause decreased air intake leading to suffocation. This can result in
death. Someone can also die from excessive laughing due to a heart attack. Thus, it is
literally possible to “die laughing.” Someone who displays cachinnation can be said to
cachinnate. Cachinnation comes from the Latin word "cachinno" meaning "to laugh