Organoid Ethics Nature Podcast Transcript PDF

Nature Podcast Transcript taken from Oct. 28, 2020 Hear the latest from the world of science, brought to you by Benjamin Thompson and Noah Baker. Host: Benjamin Thompson Welcome back to the Nature Podcast. This week, could consciousness arise in lab-grown brains? Host: Noah Baker And the impact...

Nature Podcast Transcript taken from Oct. 28, 2020 Hear the latest from the world of science, brought to you by Benjamin Thompson and Noah Baker. Host: Benjamin Thompson Welcome back to the Nature Podcast. This week, could consciousness arise in lab-grown brains? Host: Noah Baker And the impacts of cuts to a pioneering diversity initiative. I’m Noah Baker. Host: Benjamin Thompson And I’m Benjamin Thompson. [Jingle] Host: Noah Baker First up on the show this week, reporter Ali Jennings has been asking whether lab-grown mini- brains could become conscious and exploring the ethical concerns that question raises. Interviewer: Ali Jennings A dull, grey blob the size of a pinhead floats in a petri dish on a lab bench. The blob is made up of thousands of living, communicating brain cells. This is a cerebral organoid, and neuroscientists across the world are growing these structures in the lab to better understand the human brain. Interviewee: Madeline Lancaster The way that we accomplish this is by starting with stem cells, and then we essentially provide the right sort of environment to support growth of brain tissue but not other organ types so that what ends up happening is you have these 3D balls of tissue that look a lot like the developing human brain in certain ways. Interviewer: Ali Jennings This is Madeline Lancaster, an organoid researcher from the University of Cambridge in the UK. Madeline was the first person to grow a brain organoid back in 2010, and now she uses them to study brain development and disease. Interviewee: Madeline Lancaster The human brain is hugely enlarged and very complex, and that gives us our unique cognitive capability but it also makes us more susceptible to neurological conditions that are not very well modelled in, for example, mice. So, brain organoids are especially useful for looking at human- specific features of the brain and for modelling those types of neurological conditions. Interviewer: Ali Jennings Right now, researchers can’t grow brain organoids more than a centimetre in length, and they lack much of the complex internal structure of fully formed brains, even those of simpler creatures like fruit flies. But as the field matures, some researchers are working on ways to increase these organoids’ size and complexity, which raises an important question. Could such bundles of brain tissue ever become complex enough to be conscious? Interviewee: Anil Seth I don’t think it can be ruled out that a cerebral organoid could achieve consciousness. I think it’s entirely possible that as organoids develop in complexity and similarity to human brains that they could have conscious experiences. Interviewer: Ali Jennings Anil Seth works on cognitive and computational neuroscience at the University of Sussex in the UK. Anil thinks that if organoids were to become sufficiently complex, the activity they display could become more similar to that of conscious humans. The problem, according to Anil, is that we don’t know exactly what kind of complexity could lead to consciousness. Interviewee: Anil Seth You could say that being more similar in terms of neuroanatomy and neurophysiology to human brains, well, that’s the right kind of complexity. But then there’s also the possibility that you can have organoids of some kind of complex structure that’s different from the human brain but that is also sufficient for consciousness. Interviewer: Ali Jennings And this raises an even bigger question. If a future organoid were to develop consciousness, how could you tell? Interviewee: Anil Seth The real challenge with organoids, of course, is they’re just isolated mini-brains. They don’t have any natural behaviour, so the only way to make an inference about whether an organoid might be conscious is through the analysis of its brain dynamics. We can measure the electrical activity of a cerebral organoid and compare it to the kinds of patterns that we see in different conscious states in humans. Interviewer: Ali Jennings Assessing consciousness in humans is tough. Alongside measuring electrical activity, brain imaging of patients in vegetative states has also revealed conscious-like brain activity. But neither method is completely fool proof. And even if there were a clear marker for consciousness in humans, that same marker might not indicate consciousness in organoids. That said, were organoids to exhibit the kind of activity seen in the brains of conscious humans, Anil would be concerned. Although an organoid’s experience of consciousness might be very different to our own, they might still be able to experience some form of suffering and be unable to communicate it. That possibility leads Anil to believe that the field should consider guidelines for this kind of research. Interviewee: Anil Seth Because organoids are rapidly developing and not only in how sophisticated the technology is but in how many labs are conducting this kind of research, and because we don’t know any definitive way of assessing the kind of status of organoids, there is an imperative for ethical frameworks to be developed pre-emptively. Interviewer: Ali Jennings Anil is by no means the only researcher calling for guidelines in the field. Already, a committee of the National Academies of Sciences, Engineering, and Medicine in the US is examining the ethical issues associated with organoid technology. They will publish their conclusions on any possible oversight mechanisms in 2021. But Jeantine Lunshof, a philosopher and neuroethicist from Harvard University, thinks it would be premature to regulate the current field based on concerns around possible organoid consciousness. Interviewee: Jeantine Lunshof I do not believe even remotely that cerebral organoids have anything that would even approximate what we call consciousness. There are regulatory questions and those are the old ones, the classical ones like, ‘Where do you get the tissue from, the cells with which you start the process? Do you need to tell people for what experiments you’re going to use it?’ But it is not in any sense specific for the question of consciousness. Interviewer: Ali Jennings Any meaningful regulation of the field, she says, would have to rely on a firm definition of organoid consciousness, which we currently don’t have. Jeantine also points out that the very appearance of organoids – the fact that they look like mini brains – can trigger our moral intuitions where perhaps they’re unwarranted. Interviewee: Jeantine Lunshof Where we see something that looks very much like a human brain in this case, we start to ascribe properties of the human brain and our ethical considerations about human brains, so I think that is important to consider and to bring us back to the reality of research when we talk about ethical appraisal of such experiments. Interviewer: Ali Jennings There are plenty of opinions as to how this field should be regulated. Back in the lab, Madeline welcomes conversations about where ethical boundaries might be drawn in the future so as to safeguard against organoids achieving consciousness. But she’s cautious about imposing regulations on the field too soon. Interviewee: Madeline Lancaster I think it’s also very important to remember we’re having these discussions about organoids being potentially conscious or not but there are millions of actually conscious human beings out there who are actually suffering from neurological conditions that have no treatment because we don’t understand them, because the animal models have not given us the answers we need. Interviewer: Ali Jennings What’s clear is that cerebral organoids allow researchers like Madeline to study human brain cells in ways they never could before, and while future organoids could become concerningly complex, there’s plenty still to learn from the comparatively simple ones we have today. Host: Noah Baker That was reporter Ali Jennings. To read more about the potential for consciousness in brain organoids and the ethical discussions going on in the field, look for a feature article in the show notes.