It sounds kind of like a science fiction plot except that it's real: researchers have grown pea-sized brains in a lab using stem cells made from human skin.
For the experiment, published in the journal Nature, researchers took mature skin cells and reprogrammed them to be in an embryonic-like state from which they then derived their stem cells. They added some chemicals, put the mix into one of those spinning things and after 20 to 30 days the cells "organized themselves into tiny structures, called cerebral organoids."
These structures had defined brain regions, including a dorsal cortex—which makes up the largest part of our brain—and the choroid plexus, where cerebrospinal fluid is produced. The neurons were active and fired.
But they weren't exact models of the human brain. The parts were all mixed up and out of order, and some important pieces were missing, like the cerebellum. Still, the mini-brains present a lot of potential for helping us better understand diseases and disorders in the brain, like Alzheimer's for instance which has previously only been studied in rodents whose brains are not as complex as those of humans.
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