From WhatsApp groups to packed London clubs, Mahjong is suddenly everywhere. But what is it about this ancient tile game that has people hooked? Experts reveal why it could be the screen-free, sociable hobby we’ve been waiting for
Compulsive sexual behaviour is often misunderstood and isn’t simply about having a high sex drive. Experts explain the emotional triggers, underlying causes and signs that behaviour may have become difficult to control
There is no single psychological or biological profile that explains serial killing. Experts explore the complex mix of biological, psychological and social factors that may contribute to violent behaviour – and debunk some of the biggest myths