Kathmandu, July 14 -- Recently, you might have come across news reports or social media discussions about groups of students displaying unusual or unexplained behaviours in schools.

Seeing those incidents may have made you ask a simple question: Were the students pretending? What was actually going on? If you are like most people, you have probably also come across the term 'mass hysteria.' Within a short time, different explanations usually begin to circulate. Some people blame ghosts or supernatural forces, others suspect poisoning, while some dismiss those affected as pretending or seeking attention. But before we jump to conclusions, let's answer a simple question: What do we mean by 'mass hysteria'?

What many people commonly call '...