'Whether it's drugs or social media, addiction changes chemicals in our brains'

Addiction affects tens of millions of people across the world, with some more susceptible to it than others. In the past, it was seen as a moral failing but as research has progressed, it is now recognised as a disease: created cravings forming a debilitating dependence. Drugs, alcohol, social media and gambling can all change the chemicals in our brains with long-term impacts that are hard to reverse. Jocelyne Caboche, from France's CNRS research centre, gives us her perspective.