'Alien-cortical' mice: Can human brain cells grow inside animals?

'Alien-cortical' mice: Can human brain cells grow inside animals? Share'Alien-cortical' mice: Can human brain cells grow inside animals? on social media In a laboratory in California, in the United States, mice are scurrying around their cages, as mice do. But inside their brains are millions of working human neurons. Researchers at Stanford University have implanted lab-grown human cells into mice genetically engineered to lack parts of their brains, including the cerebral cortex, the outer region that plays a major role in perception, movement, decision-making and attention. Putting human brain tissue inside an animal sounds like something out of Mary Shelley's Frankenstein, but how "human" are these mice, really?