Paris (AFP) – What happens when human brain tissue implanted in a pig transmits part of the donor's self-perception and memories?
Such a scenario, which is initially unattainable, will gradually become conceivable, a group of scientists, ethicists and philosophers who on Wednesday called for a debate on the ethics of storing and using human brain matter
Brain – " Surrogates, which consist of real human cells-whether in tiny organoids grown in the lab, gray matter taken from a human patient, or brain tissue implanted in animals-are critical to the study of the organ that guides us Thought provoking.
But there are risks, 17 experts warned in a commentary published in the science journal Nature. 19659005] "As brain surrogates become larger and more sophisticated, the possibility that they have abilities similar to human sensibility may be less distant," they write.
"Such abilities could include being (to some degree) pleased with pain or distress, being able to store and recall memories, or perhaps even some sense of agency or self-awareness."  According to the group, there is a need for "clear guidelines for research" and for special supervisory committees.
They pointed to a study in which scientists called "neural activity" after shedding light on a region of a human "organoid" with eye and brain cells.
Organoids are rudimentary, three-dimensional structures that are bred from human stem cells and used to mimic features of a developing organ
The authors pointed to another study in which tiny human organoids – implanted in the brains of mice – survived and communicated with the host brain.
"Without knowing more about what consciousness is and what building blocks are needed, it might be hard to know which signals to look for in experiments," the letter says.
A proposed solution could be that researchers use anesthetics to keep animals with human brain tissue in a comatose stasis.
"Perhaps certain brain functions or a given level of brain activity indicative of a lack of capacity could be exploited ethically
Such difficult questions should not be stopped by critical research, the team
Brain surrogates can help decipher the secrets of psychiatric and neurological disorders.
"The success and social acceptance of this research In the long term, an ethical framework must now be created, while brain surrogates in the fr stages of development. "