Recognition of faces has been studied in monkeys by several groups of scientists. In human subjects face recognition can be studied using fMRI, MEG or PET or in patients who have lost this function due to trauma. Cell groups that respond to facial features are arranged as localized specific networks where some cell groups are activated by specific features of faces, like eyes or mouth region, whereas other cell groups are more active when the head is seen in profile. These cell groups are in the inferior temporal lobe. Loss of their function in both hemispheres leads to loss of face recognition (prosopagnosia). It may be complicated by simultaneous loss of ability to perceive facial expressions or this function may remain nearly normal. These two functions are thus dependent on two closely related specific cortical areas.

Loss of recognition of faces does not mean that the person does not see faces. A man who had lost facial recognition due to an accident was asked "Don't you see your face when you look in a mirror?". He answered "Of course I see a face, I see a face, not my face. The re-cognition had been lost. Since visual memory is thought to be localised within each visual cortical area, loss of recognition is likely to be related to disturbance in connections to hippocampus that controls retrieval of templates from memory.