Charles Fernyhough, Psychologist and author of The Voices Within: The History and Science of How We Talk to Ourselves, joined Sean on the show.

Listen and subscribe to Moncrieff on Apple Podcasts, Google Podcasts or Spotify.

Download, listen and subscribe on the Newstalk App.

You can also listen to Newstalk live on newstalk.com or on Alexa, by adding the Newstalk skill and asking: 'Alexa, play Newstalk'.