Scientists have grown "miniature brains" from human stem cells for the first time, in an advance that promises to revolutionise the study of diseases such as schizophrenia and autism - and raises a host of ethical questions.
Described as a "huge step forward" for neuroscience.
A consultant neurologist at the John Radcliffe Hospital in Oxford, said: "The similarities with some of the features of a human brain are really quite astounding.
