BBC Radio 4 - Understand

1. The Monroe Doctrine—US Foreign Policy in Five Doctrines

1/5 What is the 1823 doctrine, and how has it been used since by US presidents?

1/5 Justin Webb looks at five big US foreign policy shifts, from Monroe to Trump.

10/10 What more is there to learn about psychedelics? Tim Hayward makes a case for curiosity.

9/10 Who stands to profit from the commercialisation of psychedelics?

8/10 Significant barriers exist for research looking at psychedelics. Is that about to change?

7/10 Psychedelic drugs have a chequered history. How did wonder turn to fear?

6/10 Can psychedelics help the brain to learn things anew?

1/10 Tim Hayward looks at the science, culture, history - and future - of psychedelics.

5/10 Tim Hayward travels into the past to better understand today’s psychedelic research.

4/10 Tim Hayward investigates why people are travelling abroad seeking a psychedelic cure.