Joanna Moncrieff is a British psychiatrist, author and researcher who is a prominent and controversial voice in the research of depression.

Her 2002 study ‘The Serotonin Theory of Depression: A Systematic Umbrella Review of the Evidence’ concluded that there was no link between serotonin and depression, debunking the mainstream medical belief in antidepressants.

Moncrieff, whose research has drawn criticism from ‘Big pharma’ and support from fringe figures on the right, speaks to Krishnan Guru-Murthy in the latest episode of Ways to Change the World.

Produced by Silvia Maresca, Ka Yee Mak and Tom Gordon-Martin.

Pia Sinha worked in prisons for 24 years before being appointed CEO of the charity Prison Reform Trust and she describes herself as a "ridiculously optimistic" person, who believes the prisons can be made to work properly.

Sinha started her career in prison as a psychologist and went on to work in female, male prisons and institutions for young offenders. She was the governor at three prisons and later was responsible for all the women’s prisons in the country.

Sinha, who believes many of the prisoners in the UK should not be behind bars, speaks to Krishnan Guru-Murthy in the latest episode of Ways to Change the World.

Produced by Silvia Maresca, Ka Yee Mak and Tom Gordon-Martin.

Sustainability expert and professor Mike Berners-Lee argues that dishonesty in politics, business, and the media is one of the biggest barriers to tackling global crises like climate change, social inequality, and environmental destruction.

In this episode of Ways to Change the World, he talks to Krishnan Guru-Murthy about the need for a cultural shift where honesty is valued, and where deceit in public life carries real consequences. Without this, he warns, we risk making the world's biggest challenges even harder to solve.

Produced by Silvia Maresca, Ka Yee Mak, Tom Gordon-Martin.