Now you're talking: human conversation from the Neanderthals to artificial intelligence

Being able to speak is what makes us human. If you've ever felt the shock of listening to a recording of your own voice, you realise how important your voice is to your personal identity.

We judge others - and whether we trust them - not just by their words but by the way they talk: their intonation, their pitch, their accent. 'Now You're Talking' explores the full range of our voice - how we speak and how we sing; how our vocal anatomy works; what happens when things go wrong; and how technology enables us to imitate and manipulate the human voice.

Trevor Cox talks to vocal coaches who help people to develop their new voice after a gender change; to record producers whose use of technology has transformed the singing voice; and to computer scientists who replicate the human voice in their development of Artificial Intelligence.