Brain Organoids Mature for Years, Sparking Ethical Debate on Consciousness

In November 2025, scientists are making remarkable progress in brain organoid research, with some organoids now reaching an unprecedented 7 years of age. These miniature brain structures, grown from skin cells, are providing unprecedented insights into human brain development and neurological disorders.

At Harvard University, Paola Arlotta's lab has been carefully nurturing these organoids, which can contain up to 2 million neurons and exhibit electrical activity similar to the human brain. As the organoids have matured over the years, their neurons have been observed to develop and function like those in a fetal brain, a newborn, and even a young child.