Researchers in England are growing small human brains in their laboratories. Even more lab-grown-mind-boggling, they grew the brains out of human skin cells. Are these tiny brains thinking that this is pretty amazing? Not yet, but some scientists are concerned that the day is coming.
While mini-brains have been grown from stem cells for testing drugs or studying the effects of the Zika virus, this is the first time brains have been grown from non-stem cells for the purpose of studying how and why human brains are superior to the brains of other primates even though our DNA is only 1.,2 percent different from the DNA of chimpanzees. That’s according to a recent BBC Future interview with Madeline Lancaster, the research leader at the Medical Research Council (MRC) Laboratory of Molecular Medicine in Cambridge, England.
In an effort to better understand human brain development, we have developed a new model system, called cerebral organoids. Cerebral organoids, or mini-brains for short, are 3D tissues generated from human pluripotent stem cells that allow modelling of human brain development in vitro.
The cerebral organoids are really mini – only 4 millimeters across – and their development is fascinating … and frightening. Ordinary human skin cells are immersed in a kind of protein shake that causes them to grow as if they were embryonic again – only skin cells have this ability. A ball of these newly-created embryonic stem cells are placed in a Petri dish where they each begin to diversify into various body part cells. At that point, this bigger ball of cells is placed in another Petri dish containing almost no food, effectively starving the cells to death – all except the brain cells, which Lancaster says “… are really robust – I don’t think anyone knows why.”
So now they have a Petri dish of hardy survivalist brain cells. These are rewarded with a new Petri dish (this lab must make its Petri dish salesperson very rich) filled with a special jelly that acts like an embryonic skull – feeding, nurturing and molding the cells for three months until they become a tiny embryonic brain, which Lancaster says is full of firing neurons.
It’s not very special but it does tell us that we are making functional neurons and that they are acting like neurons.
Does that mean the tiny brain is thinking? Lancaster says no, and she promises that her lab will only use them as is to study neurological conditions such as autism and schizophrenia.
This is kind of a good thing, I think. I’d have some issues if I thought there was proper network formation there.
However, she admits that the next step is to grow chimpanzee brains from skin cells, which would have less ethical restrictions. Dr. Martin Coath from the Cognition Institute at the University of Plymouth warns that other scientists may not be as principled as Lancaster.
Something we have grown in the lab, but on a much simpler level than a human brain, might be hooked up to electronic eyes, ears, and hands and be taught to do something – maybe something that is as sophisticated as many simple living creatures. That doesn’t seem so far off to me.
A human brain that was ‘fully working’ would be conscious, have hopes, dreams, feel pain, and would ask questions about what we were doing to it.
What answer would they give? What answer SHOULD they give? Would it be too late. Is it already too late?