Seven years ago, researchers at Stanford University started an ambitious experiment: They began growing miniature, simplified versions of the human brain from stem cells inside a lab, then later ...

Researchers at Stanford University have transplanted human neurons into rat brains, seen them mature into hybridized brain circuits and then used them to influence the rodents’ behavior. The work ...

To create mouse-rat "chimeras," researchers injected rat stem cells into mouse embryos that lacked some genes for brain development. Creative Touch Imaging Ltd. / NurPhoto via Getty Images Scientists ...

What does it feel like to be a rat? We will never know, but some very unusual mice may now have an inkling. In a series of new experiments, bits of rat brain grew inside the brains of mice. Donor stem ...