Macaque facial gestures are more than just a reflex, study finds

Recent advances in brain-computer interfaces have made it possible to more accurately extract speech from neural signals in humans, but language is just one of the tools we use to communicate. “When my young nephew asks for ice cream before dinner and I say ‘no,’ the meaning is entirely dictated by whether the word is punctuated with a smirk or a stern frown,” says Geena Ianni, a neuroscientist at the University of Pennsylvania. That’s why in the future, she thinks, neural prostheses meant for patients with a stroke or paralysis will decode facial gestures from brain signals in the same way they decode speech.

To lay a foundation for these future facial gesture decoders, Ianni and her colleagues designed an experiment to find out how neural circuitry responsible for making faces really wor