Primates recognize complex objects such as faces with remarkable speed and reliability. Experiments in macaques demonstrated an extraordinarily simple transformation between faces and responses of cells in face patches. Six general areas of the primate and human brain that are responsible for recognizing faces were identified. Labelled ‘face patches,’ all six face patches were located in the inferior temporal (IT) cortex. Researchers found that these areas are packed with specific nerve cells that activate much more strongly when seeing faces than when seeing other objects. They called these neurons “face cells.” Rather than representing a specific identity, each face cell represents a specific axis within a multidimensional space, which researchers called the “face space.” More tomorrow.