Face cells are not passive detectors of a particular constellation of low-level visual characteristics [but] can infer the presence of a face from the association with other objects

What does a “face cell” want?’ J. Taubert, S.G. Wardle, L.G.Ungerleider. Progress in Neurobiology, September 9 2020, 101880. https://doi.org/10.1016/j.pneurobio.2020.101880

Highlights
• We review the evidence that face cells respond more to faces than objects.
• We show evidence that face patches respond to objects with illusory facial features.
• This approach connects the response of face cells to visual perception.

Abstract: In the 1970s Charlie Gross was among the first to identify neurons that respond selectively to faces, in the macaque inferior temporal (IT) cortex. This seminal finding has been followed by numerous studies quantifying the visual features that trigger a response from face cells in order to answer the question; what do face cells want? However, the connection between face-selective activity in IT cortex and visual perception remains only partially understood. Here we present fMRI results in the macaque showing that some face patches respond to illusory facial features in objects. We argue that to fully understand the functional role of face cells, we need to develop approaches that test the extent to which their response explains what we see.