An evolutionary psychology explanation for this disorder, as well as for conversion disorder more generally, is that the symptom may have been evolutionary advantageous during warfare. A non-combatant with these symptoms signals non-verbally, possibly to someone speaking a different language, that she or he is not dangerous as a combatant and also may be carrying some form of dangerous infectious disease. This can explain that conversion disorder may develop following a threatening situation, that there may be a group effect with many people simultaneously developing similar symptoms, and the gender difference in prevalence.
The theory of the story, more like.
Saying that it's "just a theory" that mass psychogenic illness is involved here is like saying that it's "just a theory" that humans evolved from non-human primates.
Note the word "seems" and "poorly understood". They don't know what this is. They are acting on a theory.
Evolution doesn't select for diseases, but sometimes it selects for generally-good traits that just happen to be error-prone.
You're skipping a very important detail in all of this.
The gender.
A sick man deserves contempt, a sick woman deserves attention and caring. Which explains why most men insist they're fine, even when at the brink of death, while women are incapacitated with the slightest headache.
In my experience, women have a tendency of succumbing to periodic ill-feeling. All of it subconscious. This brings the attention of men and family. That constant and consistent caring is habit forming and serves her well in the future when she becomes genuinely sick (or pregnant). There's your evolutionary justification.
This seems like an extreme example of the above. Probably a high status female overdid it and the rest of the females were just mimicking her behavior, all of it subconsciously. While human beings are drawn to certain behaviors instinctively, the nuts and bolts of the behavior is learned and passed down culturally. In other words, women may have a predilection toward periodic ill-feeling, but in what manner they express it is up to them ... or in this case, up to the high-status female.
Contrary to what some people say, these situations are very often a gender thing.
They tend to happen in places where girls are most limited in expression, at times when they are most limited in expression. The range of behavior considered normal for teenage girls in the US is severely limited compared to what is considered acceptable for teenage boys.
When I was in high school, I could wear the same dirty jeans every day, I could start a band that wore mouse ears and played top 40 pop songs backwards, I could spend 12 hours straight programming my computer at home, I could go to school without shoes on and completely ignore my hair unto entropy.
If I were a girl, not plucking my eyebrows would drop me to low social status at school, and depending on the school maybe even just not wearing makeup would do it. Combine that with letting your hair go to pot and locking yourself away in your room for 12 hours to program your computer, and you might be diagnosed with a psychiatric disorder like aversion or oppositional defiant at best, thrown out of the house at worst. In certain communities around the world, the triggers for deviance might start if you wore pants, or just asked to wear pants, or refused to go to the dance. I swear I've read nationally distributed news articles that start with girls choosing to wear a suit to prom, and end in death threats.
Being sick, or possessed by demons, isn't punished in society like the very real female transgressions of sloppy dressing, or being obsessed with math. Sickness and possession are signs of physical or spiritual attack that make you a victim, rather than signs of deviance that make you a threat to the social order.
Expression that relieves stress has a lot wider acceptable range in certain groups than in others. The groups with the narrowest options for expression tend to find more bizarre loopholes (sickness and religious mania), resulting in behaviors that seem odd.
As a boy, the only thing I was expected to avoid was "acting like a girl." Girls are actually expected to act like girls - whatever strange set of largely male-dictated behavior that entails.
edit: Fainting fits were once an expected behavior for women, and special furniture was required. Hysteria was thought of as a disease of female reproductive organs, and was cured through orgasm.
special furniture: http://en.wikipedia.org/wiki/Fainting_couch
the expert's opinion: http://books.google.com/books?id=ilXAFoFg1-8C
Oh, I did. I don't say things because I think they will be popular.
In fact, it isn't even Hacker News. If you drew a random group of people from any Western society and I came into the room and made that statement verbatim ... well, I would be shocked if they didn't start throwing chairs at me.
Our culture is so fundamentally sick that it not only pretends there is no significant difference between genders, it pretends there are no fundamental differences between people in general.
The differences are there and they are stark.
The absolute worst part is that after making the assumption that we are all identical, any behavior outside of the defined norm is defined as aberrant and is treated, usually with drugs. That is absolutely sick.
What's that? You can't do calculus? Well, you must be a moron. A girl that doesn't like math? We're not trying hard enough. A girl that prefers to watch The Bachelor instead of learning how to write in C? Unspeakable.
Now that is misogyny. Hatred of the feminine and its masculinization.
Those who read my comment and saw something negative in it, you're projecting. The feminine is beautiful and just because a certain behavior is disgusting in a man, doesn't make it so in a woman.
You actually think that sick men deserve contempt. And that men and women who behave identically should inspire disgust. And you insist that other people are the ones who are trying to force people into norms. Very ugly.
Yes. Just like every other sexual species on this planet has a male and female nature that dictates varied behavior, so do we.
Give me an example of a species where that isn't the case?
> and any deviation is unnatural.
Any deviation is impossible. It's hard-coded. Yes, there might be a 0.1% of the population that doesn't comply, but those are mutations.
I strongly believe that even if 1% of the population is exhibiting a behavior, it is not a deviation. It is normal. At least, normal for that 1% group.
> Your argument can be used to justify any form of prejudice that has ever existed
No. See the above. Again, if it's defined by nature, then no deviation is possible. In other words, what you're witnessing is not deviation. It is nature. On the contrary, that specific idea can be used to stop repression.
> doesn't rest on any evidence other than your own stereotypes
It's an idea derived from simple logic. Not data or stereotypes. If you're seeing a large group of people exhibiting behavior, it is natural for them. Regardless of how wrong you may think their behavior is, there is nothing wrong with it. Trying to force them to behave a certain way is wrong.
> You actually think that sick men deserve contempt.
No. However, a sickly man will be perceived as weak by other men and that will elicit contempt. Which explains why FDR desperately tried to hide the fact that he had polio and was confined to a wheel chair ... there are many many other examples of this behavior.
> And that men and women who behave identically should inspire disgust.
Men and women don't behave identically. When they do, they are forced to either by social norms or through actual threat of force. And that's sick.
Again, please provide an example of a species where the male and female behave identically?
> And you insist that other people are the ones who are trying to force people into norms.
Every day. It happens around you constantly.
I suffer quite continual pain in my back, and have a bad habit of working through an illness to the point of exhaustion. I know plenty of friends who do the same, rarely complaining.
A girl and her brother that I know are constantly ill - and moaning about the smallest thing.
So it is a personality issue, I suspect, nothing to do with gender.
This is unfortunate for men.
"Cheerleaders frequently come up in case histories of mass psychogenic illness at schools, partly because psychogenic outbreaks often start with someone of high social status. But it might also be that their enviable unity is what makes them more susceptible. In 2002, 10 students, 5 of them cheerleaders, in a rural town in North Carolina suffered from nonepileptic seizures and fainting spells. In 1952, the Associated Press reported that 165 members of the Tigerettes cheerleading squad from Monroe, La., fainted before halftime at a high-school football game in nearby Natchez, Miss."
I would love to hear someone try to speculate on an evolutionary reason for this kind of behaviour. What kind of advantage might this sort of thing have given humans in the past?