Via NPR:
They injected some human glial cells into the brains of newborn mice. The mice grew up, and so did the human glial cells. The cells spread through the mouse brain, integrating perfectly with mouse neurons and, in some areas, outnumbering their mouse counterparts. All the while Goldman says the glial cells maintained their human characteristics.
“They very much thought that they were in the human brain, in terms of how they developed and integrated,” he says.
So what are these mice like, the ones with brains full of functioning human cells? Their neural circuitry is still just the same, so they act completely normal. They still socialize with other mice and still seem interested in mousey things.
But the researchers say these mice are measurably smarter. In classic maze tests, they learn faster. “They make many fewer errors, and it takes them less time to come to the appropriate answer,” Goldman says.
To Make Mice Smarter, Add A Few Human Brain Cells : Shots – Health News : NPR
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