Brain organoids, small structures grown from stem cells, are often described as simplified models of the human brain. They lack the complexity of a full brain, which is why they have long escaped strict regulation.
However, some researchers believe that these organoids could, in the near future, reach a level of elementary consciousness, capable of experiencing sensations such as pain or pleasure.
From stem cells to organoids
Stem cells are capable of differentiating into many specialized cell types, such as neurons. In the laboratory, they are used to create organoids: miniature models of organs.
Brain organoids are obtained by culturing human stem cells under controlled conditions until they form structures resembling certain parts of the brain. These models are used to study neuronal development or certain diseases without directly using human tissues or living animals.
They are not full-fledged brains: they lack extensive connection networks, natural blood supply, and many essential functions. But they reproduce certain aspects of cellular functioning and allow observation of how neurons communicate and organize.
From organoids to consciousness
Consciousness remains difficult to define, even in humans. It is often associated with self-awareness or the ability to have subjective experiences. In the case of organoids, it would be a minimal form of consciousness, limited to elementary sensations. Researchers now use indirect methods, such as analyzing electrical activity, to infer its presence, but these tools do not provide definitive proof, as experts remind in journals like
Patterns.
Recent advances suggest the possibility of more sophisticated organoids, incorporating artificial blood vessels or additional cells such as microglia. Such improvements could enable the emergence of structures capable of generating conscious activity, forcing a revision of current ethical rules. The
International Society for Stem Cell Research already acknowledges that existing guidelines may no longer be sufficient in light of upcoming progress.
The ethical question then becomes central: what to do if an organoid develops thoughts or experiences some form of pain? In that case, these structures could be considered moral entities, on par with laboratory animals. Several scientists are therefore calling for similar oversight, with criteria to assess consciousness and adapt regulations.