What’s more, it doesn’t seem to be the case that people become desensitised to pornography, in the sense that the more you watch it, the more extreme your viewing content needs to become. When Prause and the psychologist James Pfaus of Concordia University in Quebec recently measured sexual arousal in 280 men, they found that watching more pornography actually increased arousal to less explicit material – and increased the desire for sex with a partner. In other words, it made them more, not less responsive to ‘normal’ cues, and more, not less, desirous of real physical relationships. In a 2014 review, Prause likened pornography addiction – the notion that, like a drug, the more you watch, the more, and higher doses, you crave – to the emperor who has no clothes: everyone says it’s there, but there is no actual evidence to support it.

Prause has also studied the question of relationship satisfaction more directly: did watching pornography negatively impact the quality of sexual intimacy? Working with the psychologist Cameron Staley of Idaho State University in 2013, she asked 44 monogamous couples to watch pornography alone and together, to see how it would affect feelings about their relationship. After each viewing session, the couples reported on their arousal, sexual satisfaction, perception of themselves, and their partner’s attractiveness and sexual behaviour. Prause and Staley found that viewing pornography increased couples’ desire to be with their significant other, whether they’d seen the film alone or together. Pornography also increased their evaluation of their own sexual behaviour.