This article proposes a methodological schema for engaging in a productive discussion of ethical issues regarding human brain organoids, which are three-dimensional cortical neural tissues created using human pluripotent stem cells. Although moral consideration of HBOs significantly involves the possibility that they have consciousness, there is no widely accepted procedure to determine whether HBOs are conscious. Given that this is the case, it has been argued that we should adopt a precautionary principle about consciousness according to which, if (...) we are not certain whether HBOs have consciousness—and where treating HBOs as not having consciousness may cause harm to them—we should proceed as if they do have consciousness. This article emphasizes a methodological advantage of adopting the precautionary principle: it enables us to sidestep the question of whether HBOs have consciousness and, instead, directly address the question of what kinds of conscious experiences HBOs can have, where the what-kind-question is more tractable than the whether-question. By addressing the what-kind-question, we will be able to examine how much moral consideration HBOs deserve. With this in mind, this article confronts the what-kind-question with the assistance of experimental studies of consciousness and suggests an ethical framework which supports restricting the creation and use of HBOs in bioscience. (shrink)

Human brain organoids (HBOs) are three-dimensional biological entities grown in the laboratory in order to recapitulate the structure and functions of the adult human brain. They can be taken to be novel living entities for their specific features and uses. As a contribution to the ongoing discussion on the use of HBOs, the authors identify three sets of reasons for moral concern. The first set of reasons regards the potential emergence of sentience/consciousness in HBOs that would endow (...) them with a moral status whose perimeter should be established. The second set of moral concerns has to do with an analogy with artificial womb technology. The technical realization of processes that are typically connected to the physiology of the human body can create a manipulatory and instrumental attitude that can undermine the protection of what is human. The third set concerns the new frontiers of biocomputing and the creation of chimeras. As far as the new frontier of organoid intelligence is concerned, it is the close relationship of humans with new interfaces having biological components capable of mimicking memory and cognition that raises ethical issues. As far as chimeras are concerned, it is the humanization of nonhuman animals that is worthy of close moral scrutiny. A detailed description of these ethical issues is provided to contribute to the construction of a regulative framework that can guide decisions when considering research in the field of HBOs. (shrink)

Alongside in vitro studies, researchers are increasingly exploring the transplantation of human brain organoids (HBOs) into non-human animals to study brain development, disease, and repair. This paper focuses on ethical issues raised by such transplantation studies. In particular, it investigates the possibility that they might yield enhanced brain function in recipient animals (especially non-human primates), thereby fundamentally altering their moral status. I assess the critique, raised by major voices in the bioethics and science communities, according to (...) which such concerns are premature and misleading. I identify the assumptions underlying this skeptical critique, and mention some objections against them, followed by some possible replies. I proceed to argue that the skeptical position is ultimately implausible, because it presupposes an unreasonably high standard of full moral status. My argument appeals to David DeGrazia’s idea of a “borderline person”, and to the need for consistency with existing animal research regulations. I outline the practical implications of my view for the conduct of studies that might result in the development of full moral status in a transplanted animal. I also discuss some of the ethical implications of animal enhancement (particularly of rodents) below the threshold associated with full moral status. I conclude that far from being premature, further debate on these issues is urgently needed to help clarify the prospects that a neural chimera might attain full moral status in the foreseeable future, and the level of quality of life required to make it acceptable to knowingly create such a being via HBO transplantation. (shrink)

In this paper, we outline how one might conduct a comprehensive ethical evaluation of human brain organoid transplantation in animals. Thus far, ethical concerns regarding this type of research have been assumed to be similar to those associated with other transplants of human cells in animals, and have therefore not received significant attention. The focus has been only on the welfare, moral status, or mental capacities of the host animal. However, the transplantation of human brain organoids introduces (...) several new ethical issues. Many of these are related to uncertainty regarding whether or not brain organoids might be conscious. While these concerns might not be immediately relevant, they warrant closer scrutiny. We discuss how various ethical issues are relevant to different stages of human brain organoid transplantation and can guide the ethical evaluation of research. Our examination would broaden the horizons of the debate on the transplantation of brain organoids. (shrink)

Brain Organoids in their current state of development are patentable. Future brain organoids may face some challenges in this regard, which I address in this contribution. Brain organoids unproblematically fulfil the general prerequisites of patentability set forth in Art. 3 (1) EU-Directive 98/44/ec (invention, novelty, inventive step and susceptibility of industrial application). Patentability is excluded if an invention makes use of human embryos or constitutes a stage of the human body in the individual phases (...) of its formation and development. Both do not apply to brain organoids, unless ES-cells are used. Art. 6 (1) EU-Directive 98/44/ec excludes patentability for inventions “the commercial exploitation of which would be contrary to ordre public or morality”. While there is no conceivable scenario, in which the commercial application of current brain organoids violates the ordre public, the same is not necessarily true for future brain organoids. Keeping in mind that a development of consciousness-like abilities in future brain organoids cannot be excluded and that an ability for both physical and psychological suffering has been theorized, both of which are aspects of the ordre public, certain applications of future brain organoids may constitute a violation of the ordre public and therefore lead to an exclusion of patentability. (shrink)

Brain organoid research raises ethical challenges not seen in other forms of stem cell research. Given that brain organoids partially recapitulate the development of the human brain, it is plausible that brain organoids could one day attain consciousness and perhaps even higher cognitive abilities. Brain organoid research therefore raises difficult questions about these organoids' moral status – questions that currently fall outside the scope of existing regulations and guidelines. This paper shows how (...) these gaps can be addressed. We outline a moral framework for brain organoid research that can address the relevant ethical concerns without unduly impeding this important area of research. (shrink)

It would be unwise to dismiss the possibility of human brain organoids developing sentience. However, scepticism about this idea is appropriate when considering current organoids. It is a point of consensus that a brainstem-dead human is not sentient, and current organoids lack a functioning brainstem. There are nonetheless troubling early warning signs, suggesting organoid research may create forms of sentience in the near future. To err on the side of caution, researchers with very different views about (...) the neural basis of sentience should unite behind the “brainstem rule”: if a neural organoid develops or innervates a functioning brainstem that registers and prioritizes its needs, regulates arousal, and leads to sleep-wake cycles, then it is a sentience candidate. If organoid research leads to the creation of sentience candidates, a moratorium or indefinite ban on the creation of the relevant type of organoid may be appropriate. A different way forward, more consistent with existing approaches to animal research, would be to require ethical review and harm-benefit analysis for all research on sentience candidates. (shrink)

Recent scientific and technological developments enable the generation of increasingly sophisticated organoids: three-dimensional, lab-grown stem cell-based entities that model human organs anatomi...

Any attempt at consciousness assessment in organoids requires careful consideration of the theory of consciousness that researchers will rely on when performing this task. In cognitive neuroscience and the clinic, there are tools and theories used to detect and measure consciousness, typically in human beings, but none of them is neither fully consensual nor fit for the biological characteristics of organoids. I discuss the existing attempt relying on the Integrated Information Theory and its models and tools. Then, I (...) revive the distinction between global theories of consciousness and local theories of consciousness as a thought-provoking one for those engaged in the difficult task of adapting models of consciousness to the biological reality of brain organoids. The “microconsciousness theory” of Semir Zeki is taken as an exploratory path and illustration of a theory defending that minimal networks can support a form of consciousness. I suggest that the skepticism prevailing in the neuroscience community regarding the possibility of organoid consciousness relies on some assumptions related to a globalist account of consciousness and that other accounts are worth exploring at this stage. (shrink)

Background Human brain organoids are a valuable research tool for studying brain development, physiology, and pathology. Yet, a host of potential ethical concerns are inherent in their creation. There is a growing group of bioethicists who acknowledge the moral imperative to develop brain organoid technologies and call for caution in this research. Although a relatively new technology, brain organoids and their uses are already being discussed in media literature. Media literature informs the public and (...) policymakers but has the potential for utopian or dystopian distortions. Thus, it is important to understand how this technology is portrayed to the public. Methods To investigate how brain organoids are displayed to the public, we conducted a systematic review of media literature indexed in the Nexis Uni database from 2013–2019. News and media source articles passing exclusion criteria (_n_ = 93) were scored to evaluate tone and relevant themes. Themes were validated with a pilot sample before being applied to the dataset. Thematic analysis assessed article tone, reported potential for the technology, and the scientific, social, and ethical contexts surrounding brain organoids research. Results Brain organoid publications became more frequent from 2013 to 2019. We observed increases in positively and negatively toned articles, suggesting growing polarization. While many sources discuss realistic applications of brain organoids, others suggest treatment and cures beyond the scope of the current technology. This could work to overhype the technology and disillusion patients and families by offering false hope. In the ethical narrative we observe a preoccupation with issues such as development of artificial consciousness and “humanization” of organoid-animal chimeras. Issues of regulation, ownership, and accuracy of the organoid models are rarely discussed. Conclusions Given the power that media have to inform or misinform the public, it is important this literature provides an accurate and balanced reflection of the therapeutic potential and associated ethical issues regarding brain organoid research. Our study suggests increasing polarization, coupled with misplaced and unfounded ethical concern. Given the inhibitory effects of public fear or disillusion on research funding, it is important media literature provides an accurate reflection of brain organoids. (shrink)

The possibility of consciousness in human brain organoids is sometimes viewed as determinative in terms of the moral status such entities possess, and, in turn, in terms of the research protections such entities are due. This commonsense view aligns with a prominent stance in neurology and neuroscience that consciousness admits of degrees. My paper outlines these views and provides an argument for why this picture of correlating degrees of consciousness with moral status and research protections is mistaken. I (...) then provide an alternative account of the correlation between moral status and consciousness, and consider the epistemic ramifications for research protections of this account. (shrink)

Cerebral organoid models in-of-themselves are considered as an alternative to research animal models. But their developmental and biological limitations currently inhibit the probability that organoids can fully replace animal models. Furthermore, these organoid limitations have, somewhat ironically, brought researchers back to the animal model via xenotransplantation, thus creating hybrids and chimeras. In addition to attempting to study and overcome cerebral organoid limitations, transplanting cerebral organoids into animal models brings an opportunity to observe behavioral changes in the animal itself. (...) Traditional animal ethics frameworks, such as the well-known three Rs (reduce, refine, and replace), have previously addressed chimeras and xenotransplantation of tissue. But these frameworks have yet to completely assess the neural-chimeric possibilities. And while the three Rs framework was a historical landmark in animal ethics, there are identifiable gaps in the framework that require attention. The authors propose to utilize an expanded three Rs framework initially developed by David DeGrazia and Tom L. Beauchamp, known as the Six Principles (6Ps). This framework aims to expand upon the three Rs, fill in the gaps, and be a practical means for assessing animal ethical issues like that of neural-chimeras and cerebral organoid xenotransplantation. The scope of this 6Ps application will focus on two separate but recent studies, which were published in 2019 and 2020. First, they consider a study wherein cerebral organoids were grown from donors with Down syndrome and from neurotypical donors. After these organoids were grown and studied, they were then surgically implanted into mouse models to observe the physiological effects and any behavioral change in the chimera. Second, they consider a separate study wherein neurotypical human embryonic stem cell-derived cerebral organoids were grown and transplanted into mouse and macaque models. The aim was to observe if such a transplantation method would contribute to therapies for brain injury or stroke. The authors place both studies under the lens of the 6Ps framework, assess the relevant contexts of each case, and provide relevant normative conclusions. In this way, they demonstrate how the 6Ps could be applied in future cases of neural-chimeras and cerebral organoid xenotransplantation. (shrink)

Sawai et al. (2022) provide a good summary of the bioethical debate about brain organoids with an eye toward future directions. Like many contemporary texts in bioethics, they call for engagement w...

Recent developments in 3D cultures exploiting the self‐organization ability of pluripotent stem cells have enabled the generation of powerful in vitro systems termed brain organoids. These 3D tissues recapitulate many aspects of human brain development and disorders occurring in vivo. When combined with improved differentiation methods, these in vitro systems allow the generation of more complex “assembloids,” which are able to reveal cell diversities, microcircuits, and cell–cell interactions within their 3D organization. Here, the ways in which human (...) brain organoids have contributed to demystifying the complexities of brain development and modeling of developmental disorders is reviewed and discussed. Furthermore, challenging questions that are yet to be addressed by emerging brain organoid research are discussed. (shrink)

BackgroundResearch with cerebral organoids is beginning to make significant progress in understanding the etiology of autism spectrum disorder (ASD). Brain organoid models can be grown from the cells of donors with ASD. Researchers can explore the genetic, developmental, and other factors that may give rise to the varieties of autism. Researchers could study all of these factors together with brain organoids grown from cells originating from ASD individuals. This makes brain organoids unique from other (...) forms of ASD research. They are like a multi-tool, one with significant versatility for the scope of ASD research and clinical applications. There is hope that brain organoids could one day be used for precision medicine, like developing tailored ASD drug treatments.Main bodyBrain organoid researchers often incorporate the medical model of disability when researching the origins of ASD, especially when the research has the specific aim of potentially finding tailored clinical treatments for ASD individuals. The neurodiversity movement—a developmental disability movement and paradigm that understands autism as a form of natural human diversity—will potentially disagree with approaches or aims of cerebral organoid research on ASD. Neurodiversity advocates incorporate a social model of disability into their movement, which focuses more on the social, attitudinal, and environmental barriers rather than biophysical or psychological deficits. Therefore, a potential conflict may arise between these perspectives on how to proceed with cerebral organoid research regarding neurodevelopmental conditions, especially ASD.ConclusionsHere, we present these perspectives and give at least three initial recommendations to achieve a more holistic and inclusive approach to cerebral organoid research on ASD. These three initial starting points can build bridges between researchers and the neurodiversity movement. First, neurodiverse individuals should be included as co-creators in both the scientific process and research communication. Second, clinicians and neurodiverse communities should have open and respectful communication. Finally, we suggest a continual reconceptualization of illness, impairment, disability, behavior, and person. (shrink)

Human brain organoids (HBOs), three-dimensional neural tissues derived from human pluripotent stem cells, are at the forefront of biomedical research, provoking intricate ethical quandaries (Sawai...

Organoids, in general, have become an established theme in bioethics. However, brain organoids are almost unique due to the vital and symbolic nature of the organ they reproduce, albeit partially,...

Human brain organoids are three-dimensional masses of tissues derived from human stem cells that partially recapitulate the characteristics of the human brain. They have promising applications in many fields, from basic research to applied medicine. However, ethical concerns have been raised regarding the use of human brain organoids. These concerns primarily relate to the possibility that brain organoids may become conscious in the future. This possibility is associated with uncertainties about whether and in (...) what sense brain organoids could have consciousness and what the moral significance of that would be. These uncertainties raise further concerns regarding consent from stem cell donors who may not be sufficiently informed to provide valid consent to the use of their donated cells in human brain organoid research. Furthermore, the possibility of harm to the brain organoids raises question about the scope of the donor’s autonomy in consenting to research involving these entities. Donor consent does not establish the reasonableness of the risk and harms to the organoids, which ethical oversight must ensure by establishing some measures to mitigate them. To address these concerns, we provide three proposals for the consent procedure for human brain organoid research. First, it is vital to obtain project-specific consent rather than broad consent. Second, donors should be assured that appropriate measures will be taken to protect human brain organoids during research. Lastly, these assurances should be fulfilled through the implementation of precautionary measures. These proposals aim to enhance the ethical framework surrounding human brain organoid research. (shrink)

Human brain organoids (HBOs) are novel entities that may exhibit unique forms of cognitive potential. What moral status, if any, do they have? Several authors propose that consciousness may hold the answer to this question. Others identify various _kinds of_ consciousness as crucially important for moral consideration, while leaving open the challenge of determining whether HBOs have them. This paper aims to make progress on these questions in two ways. First, it proposes a framework for thinking about the (...) moral status of entities other than paradigmatic persons. This framework identifies four qualities that ground moral status: evaluative stance, self-directedness, agency, and other-directedness. Second, we speculate on ways in which these qualities are relevant to dimensions of conscious experience that have been, or could be, identified in nonhuman animals. We further explore how these approaches could be adapted for use in HBOs, and argue that such studies, or something similar to them, will have to be performed if we wish to have empirical indications that HBOs have consciousness of a morally significant kind. We end by proposing that in our current scientific and epistemic situation, it is too soon to attribute any moral status to HBOs, but that this might change in the future. (shrink)

What consciousness exactly is remains an unsettled issue among both philosophers and biologists. Three aspects of consciousness are generally recognized: awareness consciousness (through connection...

In the last two decades, stem cell-based brain organoids have been developed to study disease mechanisms in various neurological, psychiatric, and developmental disorders. Simultaneously, there hav...

Hank Greely’s target article, “Human Brain Surrogates Research: The Onrushing Ethical Dilemma” reviews the manifold scientific and ethical questions surrounding models of human brains used i...

Mary Shelley’sFrankensteinhas captured the public imagination ever since it was first published over 200 years ago. While the narrative reflected 19th-century anxieties about the emerging scientific revolution, it also suggested some clear moral lessons that remain relevant today. In a sense,Frankensteinwas a work of bioethics written a century and a half before the discipline came to exist. This paper revisits the lessons ofFrankensteinregarding the creation and manipulation of life in the light of recent developments in stem cell and neurobiological research. (...) It argues that these lessons are becoming more relevant than ever. (shrink)

In his paper “Non-human moral status: problems with phenomenal consciousness,” Joshua Shepherd emphasized an objectivist understanding of welfare to establish the moral status of non-human entities...

Organoids are three-dimensional biological structures grown in vitro from different kinds of stem cells that self-organise mimicking real organs with organ-specific cell types. Recently, researchers have managed to produce human organoids which have structural and functional properties very similar to those of different organs, such as the retina, the intestines, the kidneys, the pancreas, the liver and the inner ear. Organoids are considered a great resource for biomedical research, as they allow for a detailed study of the (...) development and pathologies of human cells; they also make it possible to test new molecules on human tissue. Furthermore, organoids have helped research take a step forward in the field of personalised medicine and transplants. However, some ethical issues have arisen concerning the origin of the cells that are used to produce organoids and their properties. In particular, there are new, relevant and so-far overlooked ethical questions concerning cerebral organoids. Scientists have created so-called mini-brains as developed as a few-months-old fetus, albeit smaller and with many structural and functional differences. However, cerebral organoids exhibit neural connections and electrical activity, raising the question whether they are or will one day be somewhat sentient. In principle, this can be measured with some techniques that are already available, which are used for brain-injured non-communicating patients. If brain organoids were to show a glimpse of sensibility, an ethical discussion on their use in clinical research and practice would be necessary. (shrink)

The risk of creating cerebral organoids/assembloids conscious enough to suffer is a recurrent concern in organoid research ethics. On one hand, we should, apparently, avoid discovering how to distinguish between organoids that it would be permissible (non-conscious) and impermissible (conscious) to use in research, since if successful we would create organoids that suffer. On the other, if we do not, the risk persists that research might inadvertently continue to cause organoids to suffer. Moreover, since modeling some (...) brain disorders may require inducing stress in organoids, it is unclear how to eliminate the risk, if we want to develop effective therapies. We are committed to harm avoidance but hamstrung by a presumption that we should avoid research that might tell us clearly when suffering occurs. How can we negotiate this challenge and maximize the therapeutic benefits of cerebral organoid research? The author interrogates the challenge, suggesting a tentative way forward. (shrink)

In his interesting commentary, Joshua Shepherd raises two points—one related to epistemology, the other to ethics—about our article on human cerebral organoids.1 2 From the epistemological standpoint, he calls into question the need for a theory of consciousness. A theory of consciousness, for him, is not necessary because of the lack of consensus about the very nature of consciousness. Shepherd suggests that ‘given widespread disagreement, applying a theory of consciousness may not be helpful when attempting to diagnose the presence (...) of consciousness in cerebral organoids’. In Shepherd’s view, it would be better to transfer ‘concepts already under development in work on the presence and structure of consciousness in difficult marginal cases involving traumatic brain injury’.2 We could not agree more on this last point; detecting a minimal capacity for consciousness in the brain of comatose patients is a very similar challenge to inferring the presence of consciousness in cerebral organoids. Every day, as a by-product of saving many lives, intensive care medicine artificially produces thousands of brains that may remain isolated, split or fragmented; in the worst case, cortical islands, or an archipelago of islands, may survive while being disconnected from the outside world. Can these islands host some form of consciousness? That is, does it feel like anything to be a large piece of human cortex? Addressing this difficult question requires the development of general, objective brain-based indices of consciousness that are independent of sensory processing, executive functions and motor outputs.3 Consider, for example, a patient showing reflexive spontaneous behaviour, no response to command and no ability to communicate. In her brain, afferent pathways are damaged, thereby impairing the recruitment of cortical areas in response to sensory stimulation; basal ganglia, as well as other frontal structures supporting executive functions, are impaired. However, resting metabolism and significant electroencephalography …. (shrink)

Ethical deliberations are unfolding for potentially controversial organoid‐entities such as brain organoids and embryoids. Much of the ethical deliberation centers on the questionable moral status of such organoid‐entities. However, while such work is important and appropriate, ethical deliberations may become too exclusively rooted in moral status and potentially overshadow other relevant moral dilemmas. The ethical discussion on organoid models can benefit from insights brought forth by both Judith Jarvis Thomson and Don Marquis in how they attempted to advance (...) the abortion debate. To discuss other abortion ethical issues more fully, both Thomson and Marquis assumed differing moral status positions of the conceptus and followed lines of reasoning based on these moral status assumptions. We suggest a similar approach with controversial organoid‐entities like brain organoids and embryoids. To avoid overshadowing or overlooking other relevant ethical issues, ethicists ought to first assume an organoid‐entity moral status position (such as a high moral status or no moral status) and explore any possible arguments that may result from such a position. While we ought not to copy the content of Thomson and Marquis' arguments exactly for organoid‐entities, it is worthwhile to translate their arguments' overarching structures. This paper explores the relevant insights of Thomson and Marquis, how they can be translated into the organoid ethics debate, and what possible lines of inquiry may be worth exploring based on particular moral status assumptions. (shrink)

Human cerebral organoids are three-dimensional biological cultures grown in the laboratory to mimic as closely as possible the cellular composition, structure, and function of the corresponding organ, the brain. For now, cerebral organoids lack blood vessels and other characteristics of the human brain, but are also capable of having coordinated electrical activity. They have been usefully employed for the study of several diseases and the development of the nervous system in unprecedented ways. Research on human cerebral (...) organoids is proceeding at a very fast pace and their complexity is bound to improve. This raises the question of whether cerebral organoids will also be able to develop the unique feature of the human brain, consciousness. If this is the case, some ethical issues would arise. In this article, we discuss the necessary neural correlates and constraints for the emergence of consciousness according to some of the most debated neuroscientific theories. Based on this, we consider what the moral status of a potentially conscious brain organoid might be, in light of ethical and ontological arguments. We conclude by proposing a precautionary principle and some leads for further investigation. In particular, we consider the outcomes of some very recent experiments as entities of a potential new kind. (shrink)

Organoids and specifically human cerebral organoids (HCOs) are one of the most relevant novelties in the field of biomedical research. Grown either from embryonic or induced pluripotent stem cells, HCOs can be used as in vitro three-dimensional models, mimicking the developmental process and organization of the developing human brain. Based on that, and despite their current limitations, it cannot be assumed that they will never at any stage of development manifest some rudimentary form of consciousness. In the (...) absence of behavioral indicators of consciousness, the theoretical neurobiology of consciousness being applied to unresponsive brain-injured patients can be considered with respect to HCOs. In clinical neurology, it is difficult to discern a capacity for consciousness in unresponsive brain-injured patients who provide no behavioral indicators of consciousness. In such scenarios, a validated neurobiological theory of consciousness, which tells us what the neural mechanisms of consciousness are, could be used to identify a capacity for consciousness. Like the unresponsive patients that provide a diagnostic difficulty for neurologists, HCOs provide no behavioral indicators of consciousness. Therefore, this article discusses how three prominent neurobiological theories of consciousness apply to human cerebral organoids. From the perspective of the Temporal Circuit Hypothesis, the Global Neuronal Workspace Theory, and the Integrated Information Theory, we discuss what neuronal structures and functions might indicate that cerebral organoids have a neurobiological capacity to be conscious. (shrink)

Neural organoids are laboratory-generated entities that replicate certain structural and functional features of the human brain. Most neural organoids are disembodied—completely decoupled from sensory input and motor output. As such, questions about their potential capacity for consciousness are exceptionally difficult to answer. While not disputing the need for caution regarding certain neural organoid types, this paper appeals to two broad constraints on any adequate theory of consciousness—the first involving the dependence of consciousness on embodiment; the second involving (...) the dependence of consciousness on representations—to argue that disembodied neural organoids are not plausible candidates for consciousness. (shrink)

Human cerebral organoids (HCOs) are three-dimensional in vitro cell cultures that mimic the developmental process and organization of the developing human brain. In just a few years this technique has produced brain models that are already being used to study diseases of the nervous system and to test treatments and drugs. Currently, HCOs consist of tens of millions of cells and have a size of a few millimeters. The greatest limitation to further development is due to their (...) lack of vascularization. However, recent research has shown that human cerebral organoids can manifest the same electrical activity and connections between brain neurons and EEG patterns as those recorded in preterm babies. All this suggests that, in the future, HCOs may manifest an ability to experience basic sensations such as pain, therefore manifesting sentience, or even rudimentary forms of consciousness. This calls for consideration of whether cerebral organoids should be given a moral status and what limitations should be introduced to regulate research. In this article I focus particularly on the study of the emergence and mechanisms of human consciousness, i.e. one of the most complex scientific problems there are, by means of experiments on HCOs. This type of experiment raises relevant ethical issues and, as I will argue, should probably not be considered morally acceptable. (shrink)

Human brain organoids (HCOs) are laboratory-grown biological entities that have been added to the catalog of living entities for just over a decade. How they are formed and may continue to develop for some time is not irrelevant, given their peculiarity, which is that they mimic the human brain with a high degree of similarity. Revolving around this key issue is the discussion on our target article (Zilio and Lavazza 2023), for which we are grateful to all (...) the commentators. (shrink)

The complexity of the human brain creates a spectrum of sophisticated behavioral repertoires, such as language, tool use, self-awareness, symbolic thought, cultural learning, and consciousness. Understanding how the human brain achieves that has been a longstanding challenge for neuroscientists and may bring insights into the evolution of human cognition and disease states. Human pluripotent stem cells could differentiate into specialized cell types and tissues in vitro. From this pluripotent state, it is possible to generate models of the human (...) brain, such as brain organoids. The recent observation that brain organoids can spontaneously develop complex neural network activity in a dish can help one understand how neural network oscillations evolve and vary between normal and disease states. Moreover, this finding can be leveraged to other applications outside medicine, including engineering and artificial intelligence. However, as the brain model technology becomes more complex, it raises a series of ethical and moral dilemmas. This article discusses the status of this technology, some of its current limitations, and a vision of the future. (shrink)

About ten years ago, reports of lab-grown “mini brains” or “brains in a dish” appeared in the media, falling somewhere between the curious and the alarming. The trigger of these reports was a new method to grow three-dimensional neural tissue from human stem cells that recapitulates, to some degree, the early development of brain tissue. Despite their relatively small size and other limitations, such model systems capture in part the structure and functions of regions of the human brain (...) and can also be combined to form so-called assembloids. (shrink)

The generation of three-dimensional cerebral organoids from human-induced pluripotent stem cells (hPSC) has facilitated the investigation of mechanisms underlying several neuropsychiatric disorders, including stress-related disorders, namely major depressive disorder and post-traumatic stress disorder. Generating hPSC-derived neurons, cerebral organoids, and even assembloids (or multi-organoid complexes) can facilitate research into biomarkers for stress susceptibility or resilience and may even bring about advances in personalized medicine and biomarker research for stress-related psychiatric disorders. Nevertheless, cerebral organoid research does not come without its (...) own set of ethical considerations. With increased complexity and resemblance to in vivo conditions, discussions of increased moral status for these models are ongoing, including questions about sentience, consciousness, moral status, donor protection, and chimeras. There are, however, unique ethical considerations that arise and are worth looking into in the context of research into stress and stress-related disorders using cerebral organoids. This paper provides stress research-specific ethical considerations in the context of cerebral organoid generation and use for research purposes. The use of stress research as a case study here can help inform other practices of in vitro studies using brain models with high ethical considerations. (shrink)

Advances in research on human cerebral organoids (HCOs) call for a critical review of current research policies. A challenge for the evaluation of necessary research regulations lies in the severe uncertainty about future trajectories the currently very rudimentary stages of neural cell cultures might take as the technology progresses. To gain insights into organotypic cultures, ethicists, legal scholars, and neuroscientists rely on resemblances to the human brain. They refer to similarities in structural or functional terms that have been (...) established in scientific practice to validate organotypic cultures as models for brain research. In ethical discourse, however, such similarities are also used to justify assumptions about the potential risk to cause harm to HCOs. Ethicists assume that as the technology advances, organotypic cultures will increasingly resemble the human brain, raising more complex ethical issues. I argue that such reasoning is not justified given the heterogeneity of HCOs that have been modified to enable scientists to pursue their research goals. I then discuss the implications this line of thought has for advocates of the precautionary principle, focussing on those suggestions which propose adopting research regulations to the presence of bodily warning signs deemed worthy of protection. In doing so, I illustrate that the prevalent assumptions on similarity in ethical discourse ultimately risk disproportionately restricting research. I conclude that given the severe uncertainty about the technology’s future development, ethical discourse might benefit from narrowing the time frame for anticipation. (shrink)

In terms of ethical implications, Boers, van Delden and Bredenoord have made an interesting step forward with their model of organoids as hybrids, which seeks to find a balance between subject-like value and object-like value. Their framework aims to introduce effective procedures not to exploit donors and to increase their engagement, but it does not seem to take sufficient account of how organoids are used and how donors and society as a whole may want to act about such (...) uses. I will concentrate my remarks on three points that I consider relevant. The first comment concerns the so-called mini-brains. The second one is related to the issue of consent and long-term ‘control’ over the organic material granted by donors. The last comment focuses on ‘genetic minorities’. (shrink)

Synthetic Biology and Renewal of the Ethics of the Research. From the Genome Editing to Organoids of the Brains In this paper I will address the philosophical and scientific impact brought up by “synthetic biology” from the beginning of embryogeny to the fabrication of organoids, to analyze how this paradigm shift impacts on our definition of what a good life is, or should be, in rehabilitation a dialog between sciences and philosophy.

There are brains in vats (BIVs) in the actual world. These “cerebral organoids” are roughly comparable to the brains of three-month-old foetuses, and conscious cerebral organoids seem only a matter of time. Philosophical interest in conscious cerebral organoids has thus far been limited to bioethics, and the purpose of this paper is to discuss cerebral organoids in an epistemological context. In doing so, I will argue that it is now clear that there are close possible worlds (...) in which we are BIVs. Not only does this solidify our intuitive judgement that we cannot know that we are not BIVs, but it poses a fundamental problem for both the neo-Moorean (i.e. safety-based) antisceptical strategy, which purports to allow us to know that we aren’t BIVs, and the safety condition on knowledge itself. Accordingly, this case is especially instructive in illustrating just how epistemologically relevant empirical developments can be. (shrink)

The cerebral cortex controls our most distinguishing higher cognitive functions. Human‐specific gene expression differences are abundant in the cerebral cortex, yet we have only begun to understand how these variations impact brain function. This review discusses the current evidence linking non‐coding regulatory DNA changes, including enhancers, with neocortical evolution. Functional interrogation using animal models reveals converging roles for our genome in key aspects of cortical development including progenitor cell cycle and neuronal signaling. New technologies, including iPS cells and (...) class='Hi'>organoids, offer potential alternatives to modeling evolutionary modifications in a relevant species context. Several diseases rooted in the cerebral cortex uniquely manifest in humans compared to other primates, thus highlighting the importance of understanding human brain differences. Future studies of regulatory loci, including those implicated in disease, will collectively help elucidate key cellular and genetic mechanisms underlying our distinguishing cognitive traits. (shrink)