US defence secretary Pete Hegseth’s plan to livestream the execution of Nidal Malik Hasan has incurred condemnation from human rights groups and politicians on all sides. But according to Coltan Scrivner, an author and psychologist at Arizona State University and expert on morbid curiosity, people are still likely to watch in large numbers. He explains why we are drawn to dark and disturbing content, and Madeleine Finlay tells Ian Sample how consuming this kind of material can harm observers’ mental health

The sleep disorder has been the butt of jokes and a comedic plot point, but the reality of living with narcolepsy is anything but funny. Things could be about to change for people with the condition though, after the US Food and Drug Administration (FDA) approved the first ever drug to treat narcolepsy itself, rather than just its symptoms. Madeleine Finlay tells Ian Sample how the scientific breakthrough came about, and Julie Flygare, who has narcolepsy and founded the non-profit Project Sleep, explains what it is like to live with the condition and how the drug could be gamechanger