Brain in flight: Berkeley records hundreds of neurons in free-flying fruit bats

Researchers at the University of California, Berkeley, have recorded the activity of hundreds of neurons at once in the motor cortex of Egyptian fruit bats – while the animals flew freely through a large flight room. The team led by bioengineer and neuroscientist Michael Yartsev and first author Boaz Styr used tiny wireless recording devices and a multi-camera system that automatically tracks wing movements in 3D without markers. The study was published in Cell; Berkeley Engineering presented it on 13 October with a video of the motion tracking.

The result: during natural, dexterous flight, motor cortex activity is far more varied than in simplified lab tasks. Each wingbeat is performed with high accuracy and shows its own pattern of activity. "The motor cortex essentially gives a different set of instructions or corrections for each wingbeat," Styr says – for example to adjust wing symmetry or to tuck the fingers during the downstroke.

Yartsev sees implications for basic neuroscience and for the design of brain-machine interfaces meant to restore complex movements to people after a stroke or with other conditions – especially movements that require rapid feedback and precise, continuous control. The work was funded by the National Institute of Neurological Disorders and Stroke of the US National Institutes of Health and the Howard Hughes Medical Institute.