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Home / Health / Human brain cells can form complex structures in a shell – is that a problem?

Human brain cells can form complex structures in a shell – is that a problem?



Enlarge / Brains are disgusting

The premiere of the second season of Westworld is a perfect time to think about what makes us human. This is not new territory; Such questions have long been addressed in works of fiction, and they have appeared in science in the form of studies of creatures that have human-like qualities ̵

1; like consciousness – and yet not Homo sapiens . These studies raise ethical issues as to whether the subject is an animal or an AI. Last May, a consortium of bioethicists, lawyers, neuroscientists, geneticists, philosophers and psychiatrists gathered in Duke to discuss how this issue could apply to relatively new entities: a brain-grown "organoid" in a laboratory. These organoids can be either human or animal cell chimeras or human brain tissue slices. Will these laboratory-grown constructs reach any worthy consciousness?

Why Organoids?

If we ever understand the very complex brain diseases that plague people like schizophrenia, ASD and necrosis, let alone cure depression – we need research models. And to be informative, these models must be accurate representations of the human brain. But while our models are more and more similar to reality (and for the moment they are still quite far away), the problems with using them are so pronounced that they deny their beneficial Borges card.

Are psychiatric and psychiatric disorders so debilitating, is it ethical to use active human neural tissue? If we develop our ability to develop them to the point where they develop consciousness, do we still use them ethically?

Brain organoids are produced similar to other organoids – we have prepared them for the eye, intestine, liver and kidney. Pluripotent stem cells are cultured under conditions that promote the formation of specific cell types. In this case, we can make cells take on the fate of certain brain regions. These different brain regions can even be combined in limited ways. These 3D organoids contain multiple cell types and are undeniably more physiologically relevant to research than a turf of identical cells growing in a petri dish.

And they are becoming more complex; Last year, a Harvard lab recorded neuronal activity from an organoid after shedding light on a region where cells of the retina formed together with cells of the brain, indicating that the organoid could respond to an external stimulus. This is clearly not the same as feeling the need (or anything else) – but it is a significant step forward.

Chimeras were also created. In this context, it is animals – usually mice – were implanted in the human brain cells. (The implanted cells are derived from pluripotent stem cells as used for the brain organoids above – they are NOT harvested by individuals.) This, in turn, is to provide a more physiologically relevant model of brain diseases such as Parkinson's. When human glial cells were transplanted into mice, the mice performed better in some learning tasks.

The small size of the rodents used should limit the ability of human brain cells to grow, but they clearly affect the mice. Concerning human-animal blurring, the consortium writes: "We believe that decisions about which types of chimeras are allowed, or whether certain human organs that are bred in animals make animals too human-like, are ultimately made in one case taking into account the risks, benefits, and different sensitivities of people. "

Feelings

What if these entities developed sentience, whatever that means? Or the ability to feel joy or pain? Or the ability to create memories? Or a kind of self-confidence? How would we even know if they have such skills? The EEGs that are commonly used to measure awareness do not work with infants who are clearly aware and human, so they may not be applicable here as well.

Researchers have studied human brain tissue for over a century to manipulate this brain tissue, for example, to fire certain neurons. If we develop the technology to extract a person's memories from a layer of tissue, how would we treat it legally and ethically? The acceptance of this tissue would take on a completely different dimension. And since some aspects of this technology could probably work, even if the tissue donor were dead, would that change the definition of brain death?

Genetic engineers established their own rules for the use of recombinant DNA at the 1975 Asilomar Conference. Elon Musk argues that now is the time to start regulating AI. With the ongoing BRAIN initiative, it is encouraging that neuroscientists try to stay ahead of the game and develop ethical guidelines before these technologies are developed. Once these technologies arrive, there is at least a chance that we can use them responsibly.

Nature 2018. DOI: 10.1038 / d41586-018-04813-x (About DOIs). [19659016]
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