Researchers at Israel’s Bar-Ilan University and in Paris have identified neurons in the human visual cortex that can selectively respond to faces. The discovery came while studying an epileptic patient that had micro-electrodes implanted in the vicinity of the Fusiform Face Area.

https://www.timesofisrael.com/i-see-you-in-first-israeli-french-team-finds-neurons-that-respond-to-all-faces/

http://n.neurology.org/content/92/4/197