How can a good night's sleep improve your memory? Why does the answer to a crossword clue suddenly appear first thing in the morning after a night's rest? In this week's programme Claudia Hammond talks to psychologist, Kimberly Fenn about what happens in the brain when we sleep and why it can significantly improve our memory.

Hysteria or conversion disorder is surprisingly, not confined to medical history. Nearly 1 in 5 patients seen by neurologists will have symptoms like paralysis, fits or loss of vision which can't be explained neurologically. Claudia talks to neurologist, Mark Edwards and psychiatrist, Richard Kanaan about the history of conversion disorder, how common it is today, the best way to treat it and its complex causes. Also in the programme, Claudia meets the carers getting involved in mental health research and why their input is making a a difference to research projects exploring mental health across the country.