You wake up to your partner telling you that you had an entire conversation with someone named Bob last night, or your roommate mentions you were giving what sounded like a presentation in your sleep.

Sleep talking can be a slightly strange experience — whether you’re the one doing the midnight chattering or you’re sharing a bed with someone who is talking mid-snooze. But what is sleep talking and ...

Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...