Scientists grow mini-brain on the move that can contract muscle

Scientists have grown a miniature brain in a dish with a spinal cord and muscles attached, an advance that promises to accelerate the study of conditions such as motor neurone disease.

The lentil-sized grey blob of human brain cells were seen to spontaneously send out tendril-like connections to link up with the spinal cord and muscle tissue, which was taken from a mouse. The muscles were then seen to visibly contract under the control of the so-called brain organoid.

The research is the latest in a series of increasingly sophisticated approximations of the human brain grown in the laboratory – this time with something approaching a central nervous system attached.

Madeline Lancaster, who led the work at the Medical Research Council’s Laboratory of Molecular Biology in Cambridge, said: “We like to think of them as mini-brains on the move.”

The scientists used a new method to grow the miniature brain from human stem cells, which allowed the organoid to reach a more sophisticated stage of development than previous experiments. The latest blob shows similarities, in terms of the variety of neurons and their organisation, to the human foetal brain at 12-16 weeks of pregnancy.

However, the scientists said the structure was still too small and primitive to have anything approaching thoughts, feelings or consciousness.