Human brain activity has been harnessed to control gene expression in mice.

Martin Fussenegger at the Swiss Federal Institute of Technology in Zurich and his colleagues created a small, implantable cartridge containing human cells engineered to produce a protein called SEAP when exposed to light. The researchers then put this cartridge under the skin of a mouse, along with a light-emitting diode (LED).

When trained volunteers transmitted certain brain-activity patterns through a headset to a computer, the machine switched on an electrical-field generator under the mouse. The field powered up the LED implanted in the mouse, causing the cells in the implant to produce SEAP, which then passed into the bloodstream.

The device could be programmed to respond to human brain activity that predicts a seizure, for example, and prevent the episode by delivering a drug to the brain, the authors say.

Nature Commun. 5, 5392 (2014)