Human brains have been grown in a dish to help study psychiatric disorders.
Neural circuits including those of the cerebral cortex were re-created in tiny balls of cells called spheroids, grown from stem cells and developing as in the womb.
Scientists then generated abnormal circuits typical of Timothy syndrome, linked to autism, and were able to spot the defective path and correct it with drugs.
Lead scientist Dr Sergiu Pasca, from Stanford University in the US, said: “We’ve never been able to recapitulate these human brain developmental events in a dish before.
“The process happens in the second half of pregnancy, so viewing it live is challenging.
“Our method lets us see the entire movie, not just snapshots.
“Our method of assembling and carefully characterising neuronal circuits in a dish is opening up new windows through which we can view the normal development of the foetal human brain.
“More importantly, it will help us see how this goes awry in individual patients.”
The research, reported in the journal Nature, is expected to open a new window on a wide range of brain conditions including mental disorders such as schizophrenia.