The article is almost laughable!
On the one hand they say this:
article said:
“There is a popular perception that victims of ‘mass hysteria’ are somehow weak-minded or suffering from a mental disorder,” he said. “This perception needs to change, and I believe it begins with public health officials investigating these outbreaks.”.
Then spread throughout the article are subtle hints that we know its mass hysteria because most of the victims are "teenage girls"!
Most laughable is the idea that people had "evidence" that these hiccups and tics were psychogenic. Of course they didn't. You don't need any! Just an absence of any other explanation. That's why these explanations take hold and flourish so readily.
On the funnier side, apparently "psychogenic illness" flourishes when there is economic hardship and stress!
I wonder: under what conditions do "psychogenic illness explanations" flourish? Well, let's see, that would be ignorance, lack of understanding of disease and its consequences, and the capacity to link the episodes to a group that are held in some contempt (in this case, teenage girls). Think Freud, there's your case study.