Recipe for a working mini brain is here

New York: A team of US researchers has described how to make an inexpensive, working - but not thinking - miniature brain for drug testing, to test neural tissue transplants or to experiment with how stem cells work in the lab.

The little balls of brain will not perform any cogitation but can produce electrical signals and form their own neural connections -- synapses -- making them readily producible testbeds for neuroscience research, said the researchers from Rhode Island-based Brown University.

The recipe involves isolating and concentrating the desired cells with some centrifuge steps and using that refined sample to seed the cell culture in medium in a spherical mold.

The mini-brains, about a third of a millimetre in diametre, are not the first or the most sophisticated working cell cultures of a central nervous system but they require fewer steps to make and they use more readily available materials.