No more laughing! This is what a 31-year-old American woman who can’t stop laughing out loud all her life would want, for no reason and without controlling anything. And this case is not at all comical because it forced this patient to consult numerous doctors to put an end to these spasms.
Laughs or crazy laughs, up to 7 times a day
For as long as she can remember, the young woman has been the victim of fits of uncontrollable laughter. Every morning, almost at the same time, she bursts out laughing for no apparent reason. A nervous, loud, but “joyless” laugh, which exhausts him as much as it frightens him.
Especially since the feeling is not very funny: before each episode, she feels a wave of panic rising in her neck and chest. For a few seconds, it was impossible for her to speak or breathe properly. We are far from fun therapy. As a child, these attacks occurred up to seven times a day, sometimes even at night. Her parents, convinced that she was making fun, simply asked her to stop her nonsense.
A mystery that took science years to elucidate
For a long time, the tests showed nothing: normal MRI, electroencephalogram without abnormalities… Then the doctors observed the videos of his seizures. The diagnosis then came: it was gelastic seizures, an extremely rare type of epileptic seizure which manifests itself… through laughter.
These attacks are often due to a small malformation of the brain, located in the hypothalamus, a region that regulates emotions, hunger, sleep and certain hormones. A second MRI finally revealed a tiny 5 millimeter lesion: a hypothalamic hamartoma, benign, but responsible for this uncontrollable laughter.
When the brain “triggers” laughter
For neurologist Wilfrid Casseron, laughter is a phenomenon as fascinating as it is complex.
“Laughter is not just a reaction to a joke”, he explains. “It involves several areas of the brain: the frontal cortex, which plans the gesture of laughter, the cingulate cortex, where the emotional dimension is played out, and deeper regions such as the thalamus or the gray matter of the brain stem. All these areas activate together to produce this reflex.”
Normally, this mechanism provides chemical well-being: laughter releases hormones that reduce stress. But in the case of this young woman, this mechanism went wrong: the lesion of the hypothalamus acts like a faulty switch that turns on by itself.
“These hamartomas can cause anarchic electrical discharges, a bit like a short circuit“, specifies Dr Casseron. “The patient remains conscious, but cannot control anything.”
A rare disease but well known to neurologists
Gelastic seizures are so rare that even specialists barely see two or three in their career. They are difficult to detect: the affected regions are very deep, therefore invisible to the classic electroencephalogram.
“MRI is essential“insists Dr. Casseron.”Many patients are first wrongly referred to psychiatry, even though it is a neurological disorder. Before thinking that your patient is “laughing for nothing”, you need to look at his brain.
Live with laughter or be treated? It depends on the cases
To put an end to unwanted laughter, in certain cases, neurosurgical intervention can be considered, but it remains complex and risky. Indeed, the hypothalamus also controls appetite and hormones: any manipulation can have consequences on the overall balance of the body.
The young woman tried several anti-epileptic treatments, without success. As her attacks became less frequent and less severe, she chose not to continue treatment.
“In his case, laughter is not dangerous, but socially, it can be very disabling“, underlines Dr Casseron.
Today, the patient lives with this disorder, between scientific curiosity and resilience. Because if it is often said that “laughter is the best medicine”, for her, it has above all become a strange traveling companion, which science is gradually learning to understand.