Psychedelic drugs have long been been used for their mind-altering effects. Now, they are making their way into western medicine as a treatment for mental health disorders. From July, psychiatrists in Australia will be able to prescribe MDMA for post-traumatic stress disorder, making it the first country in the world to recognise psychedelics as medicines. The US could soon follow, with plans for the US Food and Drug Administration to be asked for approval to treat PTSD with MDMA this year. Ian Sample speaks to correspondent Hannah Devlin about how the science behind psychedelic therapy has progressed, and hears from Prof Celia Morgan about what treatment is actually like, what we know about the risks and what’s left to learn. Help support our independent journalism at theguardian.com/sciencepod

They can send you on a journey through waterfalls of twisting colours, turn you into a floating orb of light or make you feel like you're slowly sinking into the floor.

But increasingly the mind-altering powers of psychedelic drugs like LSD, MDMA and psilocybin aren't just being experienced at raves and in muddy fields.

In hospital clinics and research labs, they're being tested to see if they can treat a range of mental health disorders from depression to PTSD.

So far these have proved difficult to treat with conventional medicines and therapies.

Right now the evidence for psychedelic therapy looks promising, so much so that the market is already worth billions of dollars.

But exactly How effective are these drugs?

What does scientists really know about how they work and the risks they pose?

How long could it be before they reach a clinic near you?

I'm the Guardian's Science Editor Ian Sample and This is Science Weekly.

Hannah Devlin, you're a science correspondent at The Guardian and at the start of this year we did a Look Ahead episode together and 1 topic you mentioned that I thought we should dive a bit deeper into was the use of psychedelics to treat mental health problems and addiction issues.

Take me back a bit, where did this research really start?

Psychedelics has got quite a long history in medicine.

Initial interest began more looking at how psychedelic drugs could help us understand the basis for psychiatric disorders, so using them as trying to understand mental illness.

And then, over time, this interest developed in the possibility of using some of these drugs as treatments.

Probably the most famous is the studies that Albert Hoffman did with LSD in the 60s and 70s in him and others gave LSD to hundreds of patients and they were looking at everything from schizophrenia to terminal cancer patients.

And it's a little bit hard to know how to interpret some of these studies.

They weren't really done with the same ethics approvals as you would have today and also they weren't really randomised controlled trials.

But they did give some early suggestions that there might be potential for using psychedelics in medicine.

And what have some of the sort of key milestones been in terms of the research and the evidence which has started suggesting that these psychedelics could be effective for some conditions.

After those early experiments, it was almost like a dark ages period, prompted by political pressure to not do research into this field and also a change in the legal status of a lot of these substances.

But over the last decade or so, there's been a resurgence of interest.

I think 1 of the interesting things is the different ways that people are looking at commercialising those drugs and how that is starting to drive research.

So in the past, 1 of the things that has maybe held psychedelic research back a bit, aside from the legal status, is the idea that it doesn't follow the traditional drug pipeline of coming up with a new compound and patenting it and then getting it licensed.

Because these are substances that have been around for ages.

But there are some companies like Janssen that has come up with a different version of ketamine that is given in a nasal spray and they've done a large trial for a very specific preparation of that so that they can have it as a patented drug and use that to fund the research into it.

So how close are these drugs getting to being a medicine that can actually be prescribed by health professionals?

So 1 of the big studies has been a big US trial looking at MDMA for post-traumatic stress disorder.

When people were given the drug coupled with psychotherapy, they were twice as likely to recover from the condition.

And that's led Australia to approve MDMA as a treatment for post-traumatic stress disorder, although under sort of highly restricted conditions.

And it's possible that the US could licence it as a treatment as soon as this year.

In Australia, as well as being able to prescribe MDMA for PTSD, from July, psychiatrists will also be able to give patients psilocybin, the potent ingredient in magic mushrooms for treatment-resistant depression and in the US, the Oregon Health Authority recently granted a licence to the state's first psilocybin service centre.

Here in the UK, while many of these drugs remain illegal, the first postgraduate qualification in the clinical use of psychedelics is due to launch soon at the University of Exeter.

Celia Morgan, you're a professor of psychopharmacology at the University of Exeter and you're co-lead on the new postgraduate course in Psychedelic Studies.

Who's it for and what are students going to learn?

The course is for any postgraduate, so people with any first degree.

We actually had a conference at Exeter, so Breaking Convention, which is the largest psychedelics conference in Europe.

And there are lots of different people who are coming up to ask about the program, from philosophers to neuroscientists to doctors to therapists who maybe are hoping at some point to be able to deliver psychedelic therapy.

So we'll be teaching from my end about clinical trials and the therapeutic approaches psychologically that have been used in this field, as well as teaching about the neuroscience, brain imaging research, but we'll also be teaching things that are more traditionally have fallen in philosophy and anthropology.

So, things like what psychedelics help us understand about consciousness, and also ethics.

So, how do we apply ethics to this new psychedelic field?

And I noticed the course is going to touch on decolonisation.

What sort of things are you going to cover?

It's widely acknowledged that these practices and traditions owe a long lineage to indigenous peoples who have really held this knowledge for millennia.

So we want to kind of cover that within this course, how we might appropriately acknowledge that and even consider that because I'm not sure that we know how to appropriately acknowledge that at the moment.

Also improving access to these therapies.

If you look at a lot of the trials so far and some of the access in countries that have decriminalised use of psychedelics, such as in the US, it's predominantly restricted to a kind of largely white educated group of individuals.

So we want to think about how might we broaden access to these therapies to a wider range of people.

I suppose there's quite an interesting issue here whereby a lot of the sort of negative impacts of these kinds of drugs have probably been borne by non-white communities.

So now we're talking about a lot of the benefits which will probably be adopted by Western medicine, probably more likely to benefit white people more?

And I think it's 1 that really bears putting front and centre in any consideration of psychedelics.

I suppose what we've seen with the cannabis industry as it's emerged, is that people of colour have disproportionately been impacted by drug laws and criminalisation, whereas extractive capitalism, if you want to call it that, has benefited predominantly white people through the industries that have grown up around this substance.

And I think there's a real risk of that happening similarly with psychedelics, so that's something we'll be considering in the course.

Mason And do we have a good sense of how psychedelics actually are working in these cases where patients have anxiety or depression or addiction problems?

Pippa Yeah, I don't know that we have a sense exactly of how they're working.

So 1 that's been very prevalent is that these drugs have downstream effects on neuroplasticity in the brain.

So they enable the brain to become more receptive to new information.

Things like with ketamine, we see growth of spines on dendrites.

So actually forming new connections between brain cells that means the brain's more receptive to new learning.

Because people often become very entrenched in these serious mental health disorders, things like depression, addiction, people get very much stuck in a rut and it's almost impossible for them to see a way out of it.

So just that very visceral sense that your perceptions are only 1 way of looking at things I think is really helpful in therapy and something that we work with.

Celia, part of your research focuses on ketamine and alcohol addiction and you're about to start a phase 3 clinical trial across 10 NHS hospitals, typically the last step before treatment is licensed.

The trial is going to look at using ketamine together with cognitive behavioural therapy or CBT.

So give me a sense of what these sessions will look like.

So how we'll do it, if you came in for the therapy, you'd come in and have an hour and a half long session.

And so an hour of that would be kind of just a standard therapy and then a bit of mindfulness practice and then what we call preparation for the infusion.

So talking through what might happen and how to deal with things that might come up during it and then you would recover from that and then we would give people a kind of small mindfulness practice at the end while they're in a very receptive state.

Because mindfulness, for people who've tried it, it can be quite difficult, you know, just to sit still and clear your mind.

And drugs like ketamine give you a kind of actual experience of taking that observer perspective on your thoughts.

And then in our study, people come back 24 hours later for another session of therapy and that's based on the preclinical neuroscience literature that shows that these changes in neuroplasticity in the brain seem to peak 24 hours post, in our case, ketamine infusion.

And that's really what we're trying to get people to do in therapy is get people to learn new techniques and new ways of looking at things.

So they do that 3 times, they have a final therapy session.

So it's really a relatively brief intervention.

And in 1 of these sessions, how much of the drug will people get?

Are we talking about micro doses or more towards the Glastonbury end of the scale?

Probably more on the Glastonbury end of the experience, obviously within controlled clinical conditions but people will have quite strong psychedelic effects.

So certainly in our study we've had people dissolving into subatomic particles and being an amoeba or, you know, floating down their mum's ear canal in a canoe.

There's a lot of excitement around psychedelics at the moment, isn't there?

I mean, I guess not least because a lot of the existing drugs for these kinds of conditions don't seem to work very well in many patients and we haven't really had any new drugs for a long while.

I wonder, as a researcher in the field, what your view is on how much these psychedelics might be able to help?

I mean, are we, perhaps the media, in danger of hyping up these treatments?

Tahirer There's a huge potential of these medicines.

You're right, it does provide just something new for people, which in psychiatry, you know, you've not had for 60, 70 years really.

And seeing these drugs work with some people, they can have very transformative effects.

But I think, you know, most of them are still at a relatively early stage, but results are promising.

Drugs like psilocybin have not been through phase 3 trials yet, so we don't have that definitive evidence.

And I do think that sometimes the idea that people are having a miracle cure can be quite damaging for patients.

So they'll come thinking that they will respond to this when they might not have responded to anything else.

When they don't, that can be even worse in terms of the despair that they're already feeling with serious depression.

They work for some people, but not for everyone.

Some of the effects might not be long-lasting.

We need longer trials and bigger trials really to look at that.

Mason We don't tend to talk so much about the sort of risks and side effects of psychedelics when we're writing these kinds of stories.

Many listeners may well know someone who's had a bad trip in their past and they could obviously have a big impact on people.

What do we know about the risks of these kinds of psychedelics that are sort of finding their way into medicine?

There are emerging risks of these substances.

I mean, drugs like ketamine are well established and ketamine is quite unique amongst these drugs and that it does have a potential for people to become dependent on it.

And that has really serious consequences with things like your bladder.

The more classic drugs, the classic psychedelics like LSD and psilocybin, people do sometimes have psychotic reactions as a result of taking these substances.

When you look at the evidence, there's very little there, but I feel like it's something that maybe we need to be reporting more and investigating more because people do have very challenging experiences.

That said, it seems that when these drugs are taken in a controlled clinical setting, the risks are really minimised and a lot of these negative consequences come from people taking these drugs out in uncontrolled settings like festivals or waves.

And then there's also risks of the boundary issues, as they're called, with these substances because they do make users much more suggestible.

I mean I think that's going to be rare but it's something we need to keep an eye on and really develop very careful clinical guidelines for the use of these substances.

And are you optimistic that the UK can can get to the position where it can exploit these if they are shown to be effective?

I hope that we will get to this point in the UK.

Certainly from my experience, you know, working on these studies and we're running a few other psychedelic trials down in Exeter, we have such an interest from the psychiatry community, particularly younger psychiatrists, but across the board and mental health workers, practitioners, people are really, really eager for this new treatment and they see the benefit of it.

So I think there's a weight of interest from the clinical community.

It's whether the kind of regulatory changes happen in step with that.

And it's great having things like our new programme, you know, to be able to educate people.

I think that shows a real change in an institution like Exeter would start offering a postgraduate certificate in psychedelics.

Hannah, we just heard about some really promising research from Celia but there are a lot of questions left to answer.

Do you think all this work, all these studies and so on have been shifting our view towards psychedelics?

I mean have they become more tempered and maybe even more realistic the more we find out about them and what they can do?

I think a shift in opinion on these substances and maybe not having such a sort of value judgment on some of these things, which are after all, you know, they're chemicals, they affect what our brain's doing, but you know, if they help people get better, then that's a good thing.

I think when it comes to things like depression, where there's such a huge unmet clinical need, there's so many patients that aren't well served by the treatments that we've got, it really is worth pursuing all the research that we can into things that look like it might kind of provide another avenue and a different approach that might work for some of those patients.

And you know, it's been really obvious that some of this stuff is really filtered through to popular culture and things like the recent show 9 Perfect Strangers, which was based on a novel which involved a kind of psychedelic therapy retreat which, to be honest, didn't turn out great for the participants, but it just shows the level of interest that there is in this type of treatment.

Thanks to Hannah Devlin and Professor Celia Morgan.

If you're interested in finding out more about the new course at Exeter, we've put a couple of links on the podcast webpage at theguardian.com.

Before I go, another reminder to listen to The Guardian's Cotton Capital podcast, looking at The Guardian's links to transatlantic slavery.

In the sixth and final episode of the series, Cotton Capital editor and Guardian journalist, Maya Wolfe Robinson, looks at the subject of reparations and how The Guardian plans to address revelations unearthed in this investigation.

If you haven't already, search for Cotton Capital wherever you get your podcasts and hit subscribe.

This episode was produced by Madeline Finlay, the sound designer was Joel Cox, and the executive producers were Ellie Burey and Daniel Stephens.


Speaker 0: This is The Guardian. They can send you on a journey through waterfalls of twisting colours, turn you into a floating orb of light or make you feel like you're slowly sinking into the floor. But increasingly the mind-altering powers of psychedelic drugs like LSD, MDMA and psilocybin aren't just being experienced at raves and in muddy fields. In hospital clinics and research labs, they're being tested to see if they can treat a range of mental health disorders from depression to PTSD. So far these have proved difficult to treat with conventional medicines and therapies.

Right now the evidence for psychedelic therapy looks promising, so much so that the market is already worth billions of dollars. But exactly How effective are these drugs? What does scientists really know about how they work and the risks they pose? How long could it be before they reach a clinic near you? I'm the Guardian's Science Editor Ian Sample and This is Science Weekly.

Hannah Devlin, you're a science correspondent at The Guardian and at the start of this year we did a Look Ahead episode together and 1 topic you mentioned that I thought we should dive a bit deeper into was the use of psychedelics to treat mental health problems and addiction issues. Take me back a bit, where did this research really start?

Speaker 1: Psychedelics has got quite a long history in medicine. Initial interest began more looking at how psychedelic drugs could help us understand the basis for psychiatric disorders, so using them as trying to understand mental illness. And then, over time, this interest developed in the possibility of using some of these drugs as treatments. Probably the most famous is the studies that Albert Hoffman did with LSD in the 60s and 70s in him and others gave LSD to hundreds of patients and they were looking at everything from schizophrenia to terminal cancer patients. And it's a little bit hard to know how to interpret some of these studies.

They weren't really done with the same ethics approvals as you would have today and also they weren't really randomised controlled trials. But they did give some early suggestions that there might be potential for using psychedelics in medicine.

Speaker 0: And what have some of the sort of key milestones been in terms of the research and the evidence which has started suggesting that these psychedelics could be effective for some conditions.

Speaker 1: After those early experiments, it was almost like a dark ages period, prompted by political pressure to not do research into this field and also a change in the legal status of a lot of these substances. But over the last decade or so, there's been a resurgence of interest. I think 1 of the interesting things is the different ways that people are looking at commercialising those drugs and how that is starting to drive research. So in the past, 1 of the things that has maybe held psychedelic research back a bit, aside from the legal status, is the idea that it doesn't follow the traditional drug pipeline of coming up with a new compound and patenting it and then getting it licensed. Because these are substances that have been around for ages.

But there are some companies like Janssen that has come up with a different version of ketamine that is given in a nasal spray and they've done a large trial for a very specific preparation of that so that they can have it as a patented drug and use that to fund the research into it.

Speaker 0: So how close are these drugs getting to being a medicine that can actually be prescribed by health professionals?

Speaker 1: So 1 of the big studies has been a big US trial looking at MDMA for post-traumatic stress disorder. When people were given the drug coupled with psychotherapy, they were twice as likely to recover from the condition. And that's led Australia to approve MDMA as a treatment for post-traumatic stress disorder, although under sort of highly restricted conditions. And it's possible that the US could licence it as a treatment as soon as this year.

Speaker 0: In Australia, as well as being able to prescribe MDMA for PTSD, from July, psychiatrists will also be able to give patients psilocybin, the potent ingredient in magic mushrooms for treatment-resistant depression and in the US, the Oregon Health Authority recently granted a licence to the state's first psilocybin service centre. Here in the UK, while many of these drugs remain illegal, the first postgraduate qualification in the clinical use of psychedelics is due to launch soon at the University of Exeter. Celia Morgan, you're a professor of psychopharmacology at the University of Exeter and you're co-lead on the new postgraduate course in Psychedelic Studies. Tell us a bit about the course. Who's it for and what are students going to learn?

Speaker 2: The course is for any postgraduate, so people with any first degree. We actually had a conference at Exeter, so Breaking Convention, which is the largest psychedelics conference in Europe. And there are lots of different people who are coming up to ask about the program, from philosophers to neuroscientists to doctors to therapists who maybe are hoping at some point to be able to deliver psychedelic therapy. So we'll be teaching from my end about clinical trials and the therapeutic approaches psychologically that have been used in this field, as well as teaching about the neuroscience, brain imaging research, but we'll also be teaching things that are more traditionally have fallen in philosophy and anthropology. So, things like what psychedelics help us understand about consciousness, and also ethics.

So, how do we apply ethics to this new psychedelic field? Mason

Speaker 0: And I noticed the course is going to touch on decolonisation. What's meant by that in this context? What sort of things are you going to cover?

Speaker 2: It's widely acknowledged that these practices and traditions owe a long lineage to indigenous peoples who have really held this knowledge for millennia. So we want to kind of cover that within this course, how we might appropriately acknowledge that and even consider that because I'm not sure that we know how to appropriately acknowledge that at the moment. Also improving access to these therapies. If you look at a lot of the trials so far and some of the access in countries that have decriminalised use of psychedelics, such as in the US, it's predominantly restricted to a kind of largely white educated group of individuals. So we want to think about how might we broaden access to these therapies to a wider range of people.

Speaker 0: I suppose there's quite an interesting issue here whereby a lot of the sort of negative impacts of these kinds of drugs have probably been borne by non-white communities. So now we're talking about a lot of the benefits which will probably be adopted by Western medicine, probably more likely to benefit white people more?

Speaker 2: Yeah, no, absolutely. And I think it's 1 that really bears putting front and centre in any consideration of psychedelics. I suppose what we've seen with the cannabis industry as it's emerged, is that people of colour have disproportionately been impacted by drug laws and criminalisation, whereas extractive capitalism, if you want to call it that, has benefited predominantly white people through the industries that have grown up around this substance. And I think there's a real risk of that happening similarly with psychedelics, so that's something we'll be considering in the course.

Speaker 0: Mason And do we have a good sense of how psychedelics actually are working in these cases where patients have anxiety or depression or addiction problems?

Speaker 2: Pippa Yeah, I don't know that we have a sense exactly of how they're working. There are some theories out there. So 1 that's been very prevalent is that these drugs have downstream effects on neuroplasticity in the brain. So they enable the brain to become more receptive to new information. Things like with ketamine, we see growth of spines on dendrites.

So actually forming new connections between brain cells that means the brain's more receptive to new learning. Because people often become very entrenched in these serious mental health disorders, things like depression, addiction, people get very much stuck in a rut and it's almost impossible for them to see a way out of it. So just that very visceral sense that your perceptions are only 1 way of looking at things I think is really helpful in therapy and something that we work with.

Speaker 0: Celia, part of your research focuses on ketamine and alcohol addiction and you're about to start a phase 3 clinical trial across 10 NHS hospitals, typically the last step before treatment is licensed. The trial is going to look at using ketamine together with cognitive behavioural therapy or CBT. So give me a sense of what these sessions will look like.

Speaker 2: So how we'll do it, if you came in for the therapy, you'd come in and have an hour and a half long session. And so an hour of that would be kind of just a standard therapy and then a bit of mindfulness practice and then what we call preparation for the infusion. So talking through what might happen and how to deal with things that might come up during it and then you would recover from that and then we would give people a kind of small mindfulness practice at the end while they're in a very receptive state. Because mindfulness, for people who've tried it, it can be quite difficult, you know, just to sit still and clear your mind. And drugs like ketamine give you a kind of actual experience of taking that observer perspective on your thoughts.

And then in our study, people come back 24 hours later for another session of therapy and that's based on the preclinical neuroscience literature that shows that these changes in neuroplasticity in the brain seem to peak 24 hours post, in our case, ketamine infusion. And that's really what we're trying to get people to do in therapy is get people to learn new techniques and new ways of looking at things. So they do that 3 times, they have a final therapy session. So it's really a relatively brief intervention.

Speaker 0: And in 1 of these sessions, how much of the drug will people get? Are we talking about micro doses or more towards the Glastonbury end of the scale?

Speaker 2: Probably more on the Glastonbury end of the experience, obviously within controlled clinical conditions but people will have quite strong psychedelic effects. So certainly in our study we've had people dissolving into subatomic particles and being an amoeba or, you know, floating down their mum's ear canal in a canoe. So quite a diverse range of experiences.

Speaker 0: There's a lot of excitement around psychedelics at the moment, isn't there? I mean, I guess not least because a lot of the existing drugs for these kinds of conditions don't seem to work very well in many patients and we haven't really had any new drugs for a long while. I wonder, as a researcher in the field, what your view is on how much these psychedelics might be able to help? I mean, are we, perhaps the media, in danger of hyping up these treatments? Dr.

Mehreen

Speaker 2: Tahirer There's a huge potential of these medicines. You're right, it does provide just something new for people, which in psychiatry, you know, you've not had for 60, 70 years really. And seeing these drugs work with some people, they can have very transformative effects. But I think, you know, most of them are still at a relatively early stage, but results are promising. Drugs like psilocybin have not been through phase 3 trials yet, so we don't have that definitive evidence.

And I do think that sometimes the idea that people are having a miracle cure can be quite damaging for patients. So they'll come thinking that they will respond to this when they might not have responded to anything else. When they don't, that can be even worse in terms of the despair that they're already feeling with serious depression. They work for some people, but not for everyone. Some of the effects might not be long-lasting.

We need longer trials and bigger trials really to look at that.

Speaker 0: Mason We don't tend to talk so much about the sort of risks and side effects of psychedelics when we're writing these kinds of stories. Many listeners may well know someone who's had a bad trip in their past and they could obviously have a big impact on people. What do we know about the risks of these kinds of psychedelics that are sort of finding their way into medicine?

Speaker 2: There are emerging risks of these substances. I mean, drugs like ketamine are well established and ketamine is quite unique amongst these drugs and that it does have a potential for people to become dependent on it. And that has really serious consequences with things like your bladder. The more classic drugs, the classic psychedelics like LSD and psilocybin, people do sometimes have psychotic reactions as a result of taking these substances. When you look at the evidence, there's very little there, but I feel like it's something that maybe we need to be reporting more and investigating more because people do have very challenging experiences.

That said, it seems that when these drugs are taken in a controlled clinical setting, the risks are really minimised and a lot of these negative consequences come from people taking these drugs out in uncontrolled settings like festivals or waves. And then there's also risks of the boundary issues, as they're called, with these substances because they do make users much more suggestible. That makes them open to abuse. I mean I think that's going to be rare but it's something we need to keep an eye on and really develop very careful clinical guidelines for the use of these substances.

Speaker 0: And are you optimistic that the UK can can get to the position where it can exploit these if they are shown to be effective?

Speaker 2: I hope that we will get to this point in the UK. Certainly from my experience, you know, working on these studies and we're running a few other psychedelic trials down in Exeter, we have such an interest from the psychiatry community, particularly younger psychiatrists, but across the board and mental health workers, practitioners, people are really, really eager for this new treatment and they see the benefit of it. So I think there's a weight of interest from the clinical community. It's whether the kind of regulatory changes happen in step with that. And it's great having things like our new programme, you know, to be able to educate people.

I think that shows a real change in an institution like Exeter would start offering a postgraduate certificate in psychedelics. So yeah, reasons to be hopeful.

Speaker 0: Hannah, we just heard about some really promising research from Celia but there are a lot of questions left to answer. Do you think all this work, all these studies and so on have been shifting our view towards psychedelics? I mean have they become more tempered and maybe even more realistic the more we find out about them and what they can do?

Speaker 2: Yeah I mean

Speaker 1: I think a shift in opinion on these substances and maybe not having such a sort of value judgment on some of these things, which are after all, you know, they're chemicals, they affect what our brain's doing, but you know, if they help people get better, then that's a good thing. I think when it comes to things like depression, where there's such a huge unmet clinical need, there's so many patients that aren't well served by the treatments that we've got, it really is worth pursuing all the research that we can into things that look like it might kind of provide another avenue and a different approach that might work for some of those patients. And you know, it's been really obvious that some of this stuff is really filtered through to popular culture and things like the recent show 9 Perfect Strangers, which was based on a novel which involved a kind of psychedelic therapy retreat which, to be honest, didn't turn out great for the participants, but it just shows the level of interest that there is in this type of treatment.

Speaker 0: Thanks to Hannah Devlin and Professor Celia Morgan. If you're interested in finding out more about the new course at Exeter, we've put a couple of links on the podcast webpage at theguardian.com. Before I go, another reminder to listen to The Guardian's Cotton Capital podcast, looking at The Guardian's links to transatlantic slavery. In the sixth and final episode of the series, Cotton Capital editor and Guardian journalist, Maya Wolfe Robinson, looks at the subject of reparations and how The Guardian plans to address revelations unearthed in this investigation. If you haven't already, search for Cotton Capital wherever you get your podcasts and hit subscribe.

And that's it for today. This episode was produced by Madeline Finlay, the sound designer was Joel Cox, and the executive producers were Ellie Burey and Daniel Stephens. We'll be back on Thursday. See you then. This is The Guardian.

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Will psychedelic drugs transform mental health treatment?