Would you shock yourself to avoid being alone with your thoughts?

Being by themselves in an empty room can feel so unbearable to some people that they willingly self-harm

To be left alone with our thoughts can be torture. Insomniacs who suffer agonies as they lie awake night after night soon learn that it is far better to get up and do something - anything - rather than thrash about with only their restless mind for company. Negative emotions such as guilt, self-doubt and anxiety run amok at night. Daylight, with its promise of mundane tasks and social interaction, usually sends these monsters of our imagination scurrying back to their caves, but they can re-emerge whenever there are no external distractions to occupy the mind.

Some people will go to extraordinary lengths to prevent this from happening, as a series of experiments carried out in 2014 by psychologists at Harvard and the University of Virginia demonstrated. College students were instructed to sit by themselves for up to 15 minutes in a sparsely furnished, unadorned room and "entertain themselves with their thoughts". They were allowed to think about whatever they liked, the only rules being they should remain in their seats and stay awake. Unsurprisingly, a majority reported afterwards that they found it difficult to concentrate and their minds had wandered, with around half saying they didn't enjoy the experience.