Does your internal monologue play out on a television, in an attic, as a bickering Italian couple – or is it entirely, blissfully silent? 

Claudia, a sailor from Lichfield in her late 30s, is not Italian. She has never been to Italy. She has no Italian family or friends. And she has no idea why a belligerent Italian couple have taken over her inner voice, duking it out in Claudia’s brain while she sits back and listens.

Loevenbruck explains that, for the most part, we hear what she terms “inner language”. But not always. “You can have expanded and more condensed forms of inner speech,” she says. “People may experience them as abstract representations of language, without sound … some people say their inner voice...